一类数项级数的极限

针对复杂数项级数的极限问题,引出了一个定理.运用该定理使得求解方法变得更加简洁有效.     

A novel method to identify the scaling region for chaotic time series correlation dimension calculation

To obtain more accurate correlation dimension estimations for chaotic time series, a novel scaling region identification method is developed. First, points that obviously do not belong to the scaling region associated with the whole double logarithm correlation integral curve are removed using the K-means algorithm. Second, a point-slope-error algorithm is developed to recognize a possible scaling region. Third, the K-means algorithm is used again to further remove a small interval of interfering points in the possible scaling region to obtain a more precise scaling region. The correlation dimension of four typical chaotic attractors and five curves generated by the Weierstrass-Mandelbrot fractal function were calculated using the proposed method. These calculated values were very close to the respective theoretical fractal dimensions. Moreover, the effectiveness of our method in identifying the scaling region was compared with existing methods. Results show that our method can distinguish the scaling region objectively, accurately, automatically and quickly, making estimations of the correlation dimension more precise and affording significant improvements in nonlinear analysis.     

比较判别法的一个推广

以p-级数作为比较级数，对比较判别法进行了一个方面的推广，并用此法较方便地判别一类正项级数的收敛性。     

河南双河油田Ⅳ1-3层系微型构造研究

对微型构造的定义、类型及形成机制作了简要论述。微构造对油水的分布起着重要的控制作用。油层内的倾斜和起伏会引起油水的重新分异，其结果是正向微型构造区内形成剩余油富集区，斜面次之；负向微型构造区形成高含水区。在井网调整部署时应高度重视     

Fourier-Jacobi级数的绝对收敛点集

讨论ＦｏｕｒｉｅｒＪａｃｏｂｉ级数在（－１，１）中绝对收敛的真子集．     

On random Taylor series

This paper deals with random Taylor series whose coefficients consist of independent random variables {X _n } with the property: αE ^1/2{|X _n |²}≤E{|X _n |}<∞,E{X _n }=0 (Ån) for some positive constant α. The convergence, growth, and value distribution of the series are investigated. Supported by the National Natural Science Foundation of China (No. 101960433) Ding Xiaoqing: born in Oct. 1958, Doctoral candidate     

等比数列的几何表示及其应用

本文给出了等比数列的一种几何表示法，并给出了这种表示法在求和等方面的应用，特别地给出了等比数列无穷项和计算公式推导的一种新方法．     

从《热的解析理论》中看傅里叶分析的产生

《热的解析理论》是傅里叶的元典著作，它记栽着傅里叶级数和傅里叶积分的诞生过程。该文分析了傅里叶分析理论产生的动力等问题。表达了一个基本观点：任意函数的幂级数展开、三角函数的幂级数展开，以及谐波函数的魅力是傅里叶级数理论产生的动力所在。最后分析了傅里叶级数的历史意义与价值。     

Mie series for electromagnetic scattering of chiral metamaterials sphere

The electromagnetic scattering of chiral metamaterials is simulated with the Mie series method.Based on the spherical harmonics vector function in chiral metamaterials,the electromagnetic fields inside and outside of chiral metamaterials sphere are expanded.By applying the continuous boundary condition between the chiral metamaterials and surrounding medium,and the transformation from linearly to circularly polarized electric field components,the co-polarized and cross-polarized bistatic radar cross scattering(RCS) of chiral metamaterials sphere are given.How to overcome the instability of chiral metamaterials sphere of Mie series formula is discussed.The electromagnetic scattering of chiral metamaterials,normal media and metamaterials are compared.The numerical results show that the existence of chirality ξ of chiral metamaterials can decrease the bistatic RCS compared with the same size as normal media sphere.