查询词典 moments method

This paper reviews and summarizes the progress in this field as follows: the mathematical model and the difficulty of the analytical solutions is introduced; discusses the latest progress of the numerical solutions is discussed; the finite difference method, the Godunov method, the Boltzmann method, and the KFVS method of one-dimensional dam-break problem are introduced; the TVD method, the discontinuous finite element method, the finite volume method and characteristic method of two-dimensional dam-break problem are discussed; the applicability, the advantage and the disadvantage of each method are analyzed; and the progress in the numerical calculations of flow of fluid with free surface are presented.

回顾和总结了国内外对溃坝水流演进问题的研究进展：介绍了溃坝水流的数学模型及解析解法存在的困难，进而讨论了数值解法的最新进展；论述了求解溃坝水流一维问题的有限差分法、近似黎曼解的Godunov格式法、Boltzmann法、KFVS法和二维问题的TVD格式法、间断有限元法、有限体积法、特征线法，并分析了各种方法的适用范围和优缺点，及讨论了限制函数的使用；介绍了利用自由水面追踪方法计算溃坝水流的研究进展，并根据目前存在的不足和实际工程的需要，提出了进一步研究的方向和发展趋势。

Aimed at low-SNR infrared images,the principle,invariant property and computational methods of Pseudo-Zernike moments are analyzed,and a method for low-SNR infrared target detection based on Pseudo-Zernike moments is proposed.

针对低信噪比红外目标图像，分析了伪Zernike矩的基本原理、不变性和计算方法，提出了低信噪比红外目标检测的伪Zernike矩方法，并比较了模板匹配、Hu矩、伪Zernike矩方法的目标检测效果。

Owing to the drawbacks of analytical shimming, this paper puts forward the concept of passive numerical shimming for searching a method of compensating Bz'easily to a high level and with a low cost. Based on the magnetic field caused by a magnetic moment, the distribution of moments in a superconducting NMR imaging megnet can be determined through some pseudoinversion algorithm directly from Bz'. The moments are used to compensate Bz'.

无源数值匀场的出发点直接是不均匀磁场的磁场偏差B〓本身；无源数值匀场的基础为磁性材料的磁矩所产生的磁场；由已知B〓，通过某种逆运算，确定磁性材料的磁矩在主磁体中的分布，实施此分布，以磁性材料的磁矩所产生的磁场直接对B〓进行补偿——这便是本文提出的无源数值匀场的概念。

The method of moments approach to estimation implies imposing the population moment restrictions on the sample moments.

矩方法是将总体的矩限制应用于样本中。

This paper presents a new method to estimate unknown projections. To achieve better results, we make use of the discrete Radon transform and a set of discrete orthogonal Tchebichef polynomials to establish relationship between the projection moments and the image moments, and then estimate the unknown projections from the known projections using this relationship.

提出一种新的投影数据估计算法，利用离散Radon变换和Tchebichef正交多项式建立图像矩和投影矩之间的关系，并用这种关系从已知投影数据中估计未知投影数据，达到提高重建图像质量的目的。

In this paper, an adaptive algorithm for singular points detection is proposed, which is based on the behavior of Gaussian-Hermite moments. In order to detect singular point accurately, the distribution of Gaussian-Hermite moments of different orders of the fingerprint image in multiple scales is used. A PCA-based method is used to analyze the distribution of Gaussian-Hermite of fingerprint image.

介绍了一种基于Gaussian-Hermite矩分布属性的自适应指纹奇异点定位方法，为了准确地确定奇异点，用到了指纹图像在多种尺度下的不同阶Gaussian-Hermite矩分布，并用一种基于主分量分析(principal component analysis，简称PCA)的方法分析指纹图像的Gaussian-Hermite矩分布。

Uses the biggest strength training method (80%～100% biggest strength) adding 30% biggest strength load training method; the load combination method to make the acclivity to lie pushes the barbell training, good in uses; the biggest strength training method to the upper limb shot fast strength training effect (80%～100% biggest strength) adding the unarmed quickest speed training method and the biggest strength training method (80%～100% biggest strength) adding 60% biggest strength shoulders the training method the load combination method.

用"最大力量训练(80％～100％最大力量)+30％最大力量负荷最快速度训练法"负荷组合方法做上斜卧推杠铃训练，对推铅球上肢快速力量的训练效果好于用"最大力量(训练80％～100％最大力量)+徒手最快速度训练法"与"最大力量训练(80％～1 00％最大力量)+60％最大力量负荷最快速度训练法"负荷组合方法。

The details as follow: 1.Based on rules about form error in GB, mathematical models of form error are established including straightness error on the base of minimizing zone method、least-squares method and two dots linked method ; flatness error based on minimizing zone method、lease-squares method、diagonal line and three dots method; circularity and cylindricity error based on minimizing zone method、lease-squares method、minimum circumscribed circle and maximum inscribed circle.

具体内容如下：根据国标中形状误差的相关规定建立了各种要素评定方法的数学模型包括：直线度的最小区域法、最小二乘法、两端点连线法；平面度的最小二乘法、最小区域法、对角线法、三远点法；圆度和圆柱度的最小区域法、最小二乘法、最小外接圆法、最大内切圆法。

In this paper, mathematical analysis, linear algebra is more material as the foundation, on the basis of previous studies, will solve a number of the function extreme value methods, such as distribution method, elimination method, the discriminant method, mean inequality method, the geometric method, vector method and derivative method, and so to summarize, and on this basis is given for each method the corresponding examples to illustrate for readers to reference and understanding.

本文以数学分析、线性代数更教材为基础，在前人研究的基础上，将求解函数极值的若干方法，如配方法、消元法、判别式法、均值不等式法、几何法、向量法和导数法等等进行归纳总结，并在此基础上针对每一种方法给出相应的例子加以说明，以便读者参考和理解。

The examples show: It is not only scientific and rational approximately, but also as referenced calculational methods of threshold quanlity of increased or emendatory chemical substance in the "Identifecation of major hazard installations "(GB18218-2000) in the future, that appliance respective of TNT equivalent method, gasoline equivalent method, methane equivalent method, methl ethyl ketone peroxide equivalent method and hydrogen sulfide equivalent method for the rhrehold quanlity in the work site and store area of volatile substance, combustible liquid substance, combustible gaseous substance, active chemical substance and poisonous substance. At the same time, Comparing with the death radius method and evaluative method of combustible, volatile, poisonous mojor hazardinstalltions, hazard grading method of hazard degree grading in the chemical factory for the major hazard installations is simplerof operation and more practical of calcutating result, and have some significance on generalizer.

实例验证表明：TNT当量法、汽油当量法、甲烷当量法和过氧化甲乙酮当量法分别对爆炸性物质、易燃液体物质、易燃气体物质和活性化学物质的临界量确定，具有一定的科学性和合理性，可作为《重大危险源辨识》(GB18218-2000)中临界量数值修订和危险物质扩充时进行临界量确定的参考计算方法，同时，化工厂危险程度的重大危险源分级法与易燃、易爆和有毒重大危险源评价法和死亡半径法相比，评估过程简单易行，分级结果符合实际，具有较强的可操作性和一定的推广意义。

Salt is good, but if the salt becomes flat and tasteless, with what do you season it?

14：33 盐本是好的，盐若失了味，可用什么叫它再咸呢？

He reiterated that the PLA is an army of the people under the leadership of the Communist Party of China.

他重申，人民解放军是在中国共产党领导下的人民军队。