计算误差

In compensating error method, error Jabobin matrix has been calculated by all-differential coefficient constricting and simplified.

在误差补偿算法上，通过微分构造的方式计算出误差雅克比矩阵，简化了误差雅克比矩阵的计算量。

Polynomial fitting was used to map out the pressure distribution curve of numerica...

与通过试验数据计算出的结果相比，数值模拟计算出来的轴向力相对误差在9%以内，而经验公式计算的轴向力相对误差为14%，采用数值模拟方法计算轴向力具有更高的精度，对多级离心泵轴向力平衡的研究具有指导意义。

The computation implies that the influence of truncation error of up/downwards continuation is about 0.001 m2·s-2, the maximum error is only 0.11 m2·s-2, which can be ignored in CHAMP gravity field recovery. The influence of the reference gravity field error of up/downwards continuation is less than 0.1 m2·s-2 in general, but the maximum error can reach 1.3 m2·s-2. To reduce this error, a high-precision gravity field model should be used in the up/downwards continuation.

计算表明：延拓误差中的截断误差部分影响量级约0.001 m2·s-2，最大误差仅为0.11 m2·s-2，可完全忽略；延拓误差中的参考重力场模型误差影响随参考场选取的不同而有所差异，整体而言小于0.1 m2·s-2，但最大误差可达1.3 m2·s-2，采用高精度的参考重力场模型能大大减小延拓误差影响。

In the case of the side-glance angle of beam is zero or small,an algorithm has been developed to determine the latitude and longitude of an arbitrary pixel in an air-borne strip mode SAR image without consideration of the hypsography.

在不考虑地形起伏的情况下，从机载合成孔径雷达数据采集几何关系和成像原理的角度，针对正侧视和小斜视情况提出了计算机载SAR图像像素点经纬度的一种准确而实用的方法，给出了从雷达图像上的像素点计算其经纬度的详细过程，并结合某实际机载SAR成像参数对影响定位精度的因素包括高度测量误差，航向角、俯仰角、横滚角误差和多普勒中心、多普勒调频率误差进行了详细的分析。

The relationship between the refractive error and the initial elevation of laser beam is calculated by an example.

通过实例，计算了折射误差与激光束初始仰角的关系，计算结果表明，低仰角时折射误差大，高仰角时折射误差小。

Firstly, Wavelet-Galerkin algorithm for solving the first kind of singular integral equation with the Hilbert kernel is proposed, we use the characteristic of periodic wavelet on L~2([0,1]) and Hilbert kernel to solve and make stiff matrix lower dimensions and become sparser through thresholding,thus the cost of computation is reduced. Because of the singularity of Hilbert kernel we use Tikhonov regularization method to solve the system of stiff equation. At last the convergence and numerical result of approximate solution are given. Secondly, an approach of regularization based on Fourier is presented for sideways heat equation; we give the theory proof and error estimate.

首先，提出了含Hilbert核的第一类奇异积分方程的小波伽辽金(Wavelet-Galerkin)数值算法，该算法中利用了L~2([0，1])上的周期小波和Hilbert核的特点进行处理，使得刚性矩阵维数降低并且通过阈值使得它更加稀疏，减少了计算量；由于Hilbert核的奇异性，通过Tikhonov正则化方法求解所得到的刚性方程组，给出了收敛性和数值结果；其次，对标准的一维逆热传导方程给出了一种基于Fourier正则化方法，给出了理论证明及其误差估计，解决了文献中算法与理论误差估计的不相匹配的现象，该正则化方法不仅保留了测量数据的部分高频成份，且与文献中的算法具有同样的计算量和误差估计。

To analyze the pseudo phenomena caused by migration velocity error, the paper firstly studied the depth error between post-stack migration and prestack migration caused by same velocity error, and found the depth error was only relative to velocity error and had no direct matter with methods of depth migration (post-stack migration or prestack migration). Then the paper did numerical simulation of a complex lenticular body model with wave-equation modeling and migration, and found that the velocity error could not only induce depth error, but also could change the modality of construction and the event of subjacent layers. Furthermore, it could change the frequency of reflective event. They are the pseudo phenomena caused by migration.

从分析偏移速度误差带来的各种假象出发，本文首先对比分析了速度误差对叠后深度偏移和叠前深度偏移的影响，发现偏移剖面的深度误差仅与速度模型的误差有关系，与具体的偏移方法没有直接的关系；然后对一个复杂的透镜体模型进行了波动方程叠后正演和偏移计算，详细地讨论了不同的速度误差带来的各种假象，发现速度误差不仅会带来深度误差，而且会造成构造体的形态变化，下覆地层同向轴的扭曲，还可能引起地层同向轴的频率发生变化，给资料解释带来一定的假象。

The horizontal and vertical first derivatives of magnetic anomalies of an infinite cylinder are calculated by the cosine transform method, in which the maximum errors are -028 nT/m and 047nT/m, respectively and the percent errors are generally within -357%～327% and -194%～188%, respectively except several data of the boundary and part are bigger because of remains of Gibbus effect. The calculating curve and theoretical curve are approximately coincident, and there is no influence by effective magnetic dip angle in computing.

利用余弦变换法计算的无限长水平圆柱体磁异常水平和垂向一阶导数的最大误差分别为-028 nT/m、047 nT/m；水平一阶导数的误差一般在-357%～327%之间，垂向一阶导数的误差一般在-194%～188%之间；计算的磁异常一阶导数值与理论值大致重合，而且不受有效磁化倾角的影响。

Using the a hand-hold GPS and wireless transmitting unit to rapidly locate the fire and determine the rate of fire spread, which also offered an indispensable way of verifying the speed of forest fire appealing. Discussing the representation and Computing Method of the simulate calculation error based on the thorough investigation of the sources of simulate calculation error. Pointing out that the speed and directional error are the root of forest fire appealing simulates error. Thus increasing the parameter of error correction is an effect way of reducing systematicsimulationerrors.

4提出了一种利用手持GPS和无线传输设备来快速测定火场位置和林火实际蔓延速度的方法，为林火蔓延模拟速度验证提供了必要的手段；对林火蔓延模拟误差的来源进行了全面分析，探讨了林火蔓延误差的表现形式和计算方法，指出了林火蔓延速度误差和蔓延方向误差是林火蔓延误差产生的根源，提出了通过增加系统误差修正参数来减少系统模拟误差的有效方法。

Based on the measure of sand geometry in M Block and comparison of results calculated with Spherical, Exponential and Gaussian Model, it is concluded that different variogram models get very different variogram range in major and minor direction.

在详细解剖M油田的砂体几何形态的基础上，对比分析球模型、指数模型和高斯模型的计算结果，3种模型计算的变差函数长变程误差15％，短变程误差25％，方向也不一样；同时运用不同模型计算的砂体体积亦有较明显的差别：砂体越发育，砂体连通性越强，不同模型计算的砂体体积相差越小；砂体越不发育，砂体连通性越差，不同模型计算的砂体体积相差越大。

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％。