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1.
在二阶线性齐次微分方程边值问题相似构造解式的基础上,首先利用相似构造法求解Bessel方程和变型的Bessel方程边值问题的解,然后建立了均质油藏的渗流规律的数学模型,再将均质油藏的渗流数学模型转换成变型的Bessel方程的边值问题,利用二阶线性齐次微分方程边值问题的相似构造法求解均质储层渗流的数学模型.最后通过Matlab编程进行图版分析,展示实例的函数解.这将极大地方便试进分析软件的编制,也提高了石油工作者的效率.  相似文献   

2.
关于包含奇-偶下标第二类契贝谢夫多项式的恒等式   总被引:7,自引:0,他引:7  
给出了一类包含偶下标第二类契贝谢夫多项式和一类包含奇下标第二类契贝谢夫多项式求和的递推公式,得到了一些包含偶下标第二类契贝谢夫多项式和奇下标第二类契贝谢夫多项式的恒等式.  相似文献   

3.
有限域上多项式型的低差分均匀度函数在分组密码的非线性组件S盒中有着重要的作用.为了增强S盒的混淆作用,应用在S盒中的函数应具有较高的非线性度和较高的代数次数.文章通过改变Dobbertin类的单项式函数在有限域F_(2n)的一个子域上的函数值,构造了两类新的多项式型的低差分均匀度函数,并确定了这两类多项式型函数的代数次数和第二类函数的非线性度.  相似文献   

4.
韩惠丽  龚亚方 《数学杂志》2003,23(3):257-262
基于对未知函数用适当的正交多项式进行逼近,本文讨论了带变系数的第二类奇异积分方程的Galerkin解法,证明了逼近解的存在唯一性,给出了逼近解在带权L^2模和一致模下的误差估计.  相似文献   

5.
张培璇 《数学研究》1996,29(1):29-33
本文基于第二类Chebyshev多项式,构造双正交级数,给出其核函数的Christoffel-Darboux型公式,讨论其部分和与相应的Fourier级数的部分和之间的关系,导出了部分和的偏差估计.  相似文献   

6.
崔明根 《计算数学》1981,3(3):277-280
近在[3]中验证了该多项式对这类函数的逼近效果也是很好的,它与最佳逼近多项式的逼近效果不相上下. 关于第二类eeb多项式零点作插值点时,稳定插值多项式(我们称其为第二类Hermite-Fejer多项式)的结果不多.最近见到Bojanic,Prasad和Saxena的结果,他们验证了第二类 Hermite-Fejer多项式(表达式的推导见[5]中的(1)):  相似文献   

7.
记Un(z)是第二类Chebyshev多项式,伴随函数,这里讨论基于的双正交级数和其共轭级数的部分和逼近问题。  相似文献   

8.
基于保角变换技术和Faber级数展开,研究了含任意形状夹杂或缺陷的无限大Reissner板弯曲问题.将变换域中单位圆内、外解析函数分别展开成Faber级数,并将波动函数展开成第一类和第二类修正的n阶Bessel函数;利用边界位移、剪力和弯矩连续性条件得到问题的高阶线性方程组.以含椭圆形夹杂和缺陷的无限大Reissner板柱面弯曲为例,进一步给出了数值算例和理论分析.结果表明,对于软夹杂,板内力矩随夹杂与板厚尺寸比a/h变化非常敏感;在含硬夹杂条件下,板内力矩随夹杂尺寸变化相对不敏感.  相似文献   

9.
本文主要的目的是利用广义Fibonacci多项式的生成函数及其偏导数来研究第二类Cheby-shev多项式卷积的计算,并给出—个有趣的计算公式.  相似文献   

10.
许贵桥  李同胜 《数学杂志》2005,25(2):151-156
本文证明多元多项式周期样条空间是某些多元周期光滑函数类的关于Kolmogorov n-宽度的弱渐近极子空间.给出了广义周期Besov类的一种推广,得到了空间元素的一种表示定理,不仅给出了一种多元周期多项式样条算子.而且证明了所得的结果.  相似文献   

11.
In this paper our aim is to present an elementary proof of an identity of Calogero concerning the zeros of Bessel functions of the first kind. Moreover, by using our elementary approach we present a new identity for the zeros of Bessel functions of the first kind, which in particular reduces to some other new identities. We also show that our method can be applied for the zeros of other special functions, like Struve functions of the first kind, and modified Bessel functions of the second kind.  相似文献   

12.
Root of characteristic equation for cylindrical Bessel equation eigenvalue prob-lems on general interval is of great real physical importance at engineering and physical. First, the characteristic equation of cylindrical Bessel equation eigenvalue problem on general interval is given, second, by mean of compared method, we obtaining roots of characteristic equation with Matlab program is discussed.  相似文献   

13.
Approximation problems for functions on the half-line [0,+∞) in a weighted L p -metric are studied with the use of Bessel generalized translation. A direct theorem of Jackson type is proven for the modulus of smoothness of arbitrary order which is constructed on the basis of Bessel generalized translation. Equivalence is stated between the modulus of smoothness and the K-functional constructed by the Sobolev space corresponding to the Bessel differential operator. A particular class of entire functions of exponential type is used for approximation. The problems under consideration are studied mostly by means of Fourier-Bessel harmonic analysis.  相似文献   

14.
In this paper, we define a class of strongly connected digraph, called the k-walk- regular digraph, study some properties of it, provide its some algebraic characterization and point out that the 0-walk-regular digraph is the same as the walk-regular digraph discussed by Liu and Lin in 2010 and the D-walk-regular digraph is identical with the weakly distance-regular digraph defined by Comellas et al in 2004.  相似文献   

15.
In this article, a numerical technique is presented for the approximate solution of the Bagley–Torvik equation, which is a class of fractional differential equations. The basic idea of this method is to obtain the approximate solution in a generalized form of the Bessel functions of the first kind. For this purpose, by using the collocation points, the matrix operations and a generalization of the Bessel functions of the first kind, this technique transforms the Bagley–Torvik equation into a system of the linear algebraic equations. Hence, by solving this system, the unknown Bessel coefficients are computed. The reliability and efficiency of the proposed scheme are demonstrated by some numerical examples. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

16.
A first kind Fredholm integral equation with nondegenerate kernel is given, which particular solution is the Bessel function of the first kind. This equation is solved by means of Mellin transform pair.  相似文献   

17.
In this paper necessary and sufficient conditions are deduced for the close‐to‐convexity of some special combinations of Bessel functions of the first kind and their derivatives by using a result of Shah and Trimble about transcendental entire functions with univalent derivatives and some newly discovered Mittag–Leffler expansions for Bessel functions of the first kind.  相似文献   

18.
The Integration of Bessel Functions   总被引:2,自引:0,他引:2  
Starting with the well-known differential and recurrence relationsof Bessel functions, a formula is obtained by means of whichthe nth-order derivative of a Bessel function of order p canbe expressed in terms of the Bessel function of order p andits first derivative, the function and its derivative beingmultiplied by polynomials in 1/x, x being the argument. By usingthe method in reverse, the integral of a Bessel function canbe expressed in terms of the Bessel function and its derivative,which are multiplied by series in x if p is even, or polynomialsin 1/x if p is odd. These formulae are more convenient for computationthan the well-known formulae involving series of Bessel functions.  相似文献   

19.
The paper is devoted to the study of the fractional integral operator, which is a negative real power of the singular wave operator generated by Bessel operator using weighted generalized functions. We give conditions for this operator to be bounded in appropriate spaces, obtain formula for the Hankel transform of this operator, and get formula of connection between this operator and natural degree of singular wave operator generated by Bessel operator.  相似文献   

20.
The transmutation (transformation) operator associated with the perturbed Bessel equation is considered. It is shown that its integral kernel can be uniformly approximated by linear combinations of constructed here generalized wave polynomials, solutions of a singular hyperbolic partial differential equation arising in relation with the transmutation kernel. As a corollary of this result an approximation of the regular solution of the perturbed Bessel equation is proposed with corresponding estimates independent of the spectral parameter.  相似文献   

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