查询词典 random field

Using the formula about the magnetic flux density induced by coil which deduced by Biot-Savart law,this paper deduces the formula about random point's magnetic flux density of hollow column solenoid and deduces the formulas about axial specific magnetic force and radial specific magnetic force by using the field gradient expression of binary function and the expression of specific magnetic force .

利用二元函数的梯度公式及比磁力公式可以得到磁性颗粒在厚壁圆环线圈所产生的磁场任意点的比磁力的轴向分量和径向分量。

The method of geopotential field conversion on random curve surface is presented by use of conformal mapping in this paper.

本文提出了一种用保角变换进行任意曲面位场转换的方法，并给出了模型例子，讨论了产生误差的原因及应用中应注意的问

PSO is a population-based optimization algorithm, which mimics the social behavior of animals in a flock. It makes use of individual and group memory to update each particle position allowing global and local search optimization. The objective function considered was the total weight of the structure subjected to stresses, displacements and forces constraints. The effects of the parameters were investigated as well and such combination of tuning parameters promote a better global search behavior avoiding premature convergence while rapidly converging to the optimal solution. Results showed the effectiveness of the proposed method by comparing with ANSYS Design Optimization Tool (zero-order method). The PSO with the tuning parameters makes it an ideal method for offshore wind turbines foundations optimization tasks.(2) A reliability analysis method for pile foundation bearing axial loads based PSOThe performance function of pile foundation's axially bearing capacity sometimes is nonlinear and complex, on the basis of geometric meaning of structural reliability index, an optimum model with PSO for structural reliability analysis under arbitrary random variables was established, The PSO algorithm is very efficient to solve global optimization problemsIts use in structural reliability field presents not only the advantage of its facility of implementation, but also the possibility to obtain the design point and the failure probability with a good accuracy. In addition, PSO is a zero order algorithm, for no derivative is necessary for its implementation.

本文的研究针对桩式海上风机基础结构的特点，在国内外有关研究成果的基础上对海上风机基础结构优化设计理论和可靠度方法一些相关问题进行了较为深入的研究，具体做了以下几个方面的工作：(1)基于粒子群优化的桩式海上风机基础确定性优化设计方法桩式海上风机基础的优化设计是一个复杂的、非线性约束的优化问题，针对传统的基于梯度信息的优化方法在处理非线性问题中易陷入局部最优解的问题，本文将一种耦合惩罚函数的PSO算法引入到海上风机基础结构概念设计中，PSO算法是从群体动物聚集觅食这一活动中受到启发而发展的，该算法利用个体和群体的信息共享不断改进自身的位置从而进行局部和全局最优搜索，本文中以桩和三脚架连接段直径及壁厚为设计变量，以基础总重量作为优化的目标函数，在给定的约束条件下建立了三脚架基础优化数学模型，另外本文还研究了PSO参数变化对结果的影响，协调的参数组合可以避免陷入早熟收敛而能够快速的获得全局的最优解，通过与ANSYS优化模块的计算结果比较验证了该方法的有效性，本方法为海上风机基础的确定性设计提供了一条有效的途径。

Circuit principles, analogue circuit, digit circuit which laid me a solid foundation of circuit for the study of communication; the study of electronic circuit of communication provided me with the working principles of analog communication system; the study on communication theory made me grasp the working methods of digital communication; the study on electromagnetic field, electromagnetic wave and aerial let me know that how signals travel through signal paths and how to apply signal and linear system, random signal and system to the research of noise's impact on signals

学习了电路原理、模拟电路、数字电路打下了学习通信的电路基础；学习了通信电子线路掌握了模拟通信系统的工作原理；学习了通信原理掌握了数字通信的工作方法；学习了电磁场与电磁波、微波与天线了解了信号如何在信道中传输；学习了信号与线性系统和随机信号与系统来研究噪声对信号的影响。

By introducing diffractive surface,with the particular negative dispersive and the power of realizing random-phase modulation,in optical system,a hybrid diffractive-refractive optical system of see-through head-mounted display for augmented reality with 26 mm eye relief,12 mm exit pupil and 20°×15.4° field-of-view is designed.

利用衍射光学元件独有的负色散性质和可实现光波面任意相位调制的特点，在光学系统中引入衍射面，设计了出瞳距离为26 mm，出瞳直径为12 mm，视场角为20°×15.4°的用于增强现实的折/衍混合穿透式双通道头盔显示器的光学系统。

To meet the needs of detection of space faint objects for a telescope with large aperture and short focal,a binding drawtube telescope scheme to detect space object is presented to overcome the shortcomings that focal length grows and field of view shrinks with the increasing of aperture size in traditional telescope for space detection.The software methods are used to stack collected images to restrain background random noises and to improve image Signal to Noise Ratio and the detecting ability of the whole system.

为了满足空间暗弱目标探测对大口径、短焦距望远镜系统的要求，克服普通望远镜随着口径的增加焦距变长、视场变小的不足，提出了将多镜筒捆绑在一起对同一空域进行观测，通过软件的方式对采集的图像进行叠加来抑制背景随机噪声、提高图像的信噪比和系统的整体探测能力的设想。

Also studies in this field in China would be a new exploration of research with Chinese characteristics, and would be a new research area for educational psychology. In this study, from the perspective of educational psychology, using integrated research orientation, and adopting the methods used in cultural psychology, ethnopsychology, utilizing open questionnaire investigation, closed questionnaire investigation, expert consultation, case interview, random suffer method, analytical hierarchy process, exploratory factor analysis and confirmatory factor analysis etc., the researcher analyzed the structures of civilized mentality, and the psychological features of civilized mentality among teenagers in modern Chinese cities.

因此，植根于中国文化和中华民族文明心理思想的土壤之中，从当代中国青少年文明心理的现状、现代人的素质要求、和谐社会构建需要等实际出发来研究我国当代青少年的文明心理的结构及其特征，是心理科学密切联系社会现实需要，进行中国化研究的一种新的探索和任务，是教育心理学需要研究的现实而迫切的新领域。

The experimental results show that the distribution founction p of the whole signal group and the different pulse width subsets all fit the lognormal distribution with very high precision in the amplitude's field of definition (V0,VM) under the condition of the big samples, which indicates that the random signal group has the statistical fractal (self-similarity) characteristic.

实验数据表明，在大样本条件下，脉冲信号集合整体及不同脉宽信号子集的p 函数在幅度定义域(V0，VM)内均以很高的精度满足对数正态分布形式，即该随机脉冲信号群具有统计分形特征。

The content is : theory of polynomials and finite field; psudo-random sequence and stream cipher; textbook cryptography and modern cryptography.

主要的内容有：多项式理论与有限域理论；伪随机序列与流密码；教科书密码与现代密码。

Three turbulent models used recently have been analyzed. On the basis of turbulent random theory, the k-εtwo equations turbulent model has been modified by nonisotropic hypothesis, to accommodate the nonisotropic property of flow field.

重新推导了雷诺应力表达式，将湍动粘性系数用一个二阶张量形式表示，以适应流场的各向异性性质，并对ε输运方程的生成项做了修正。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。