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1.
We present a construction of a wavelet-type orthonormal basis for the space of radial $L^2$-functions in {\bf R}$^3$ via the concept of a radial multiresolution analysis. The elements of the basis are obtained from a single radial wavelet by usual dilations and generalized translations. Hereby the generalized translation reveals the group convolution of radial functions in {\bf R}$^3$. We provide a simple way to construct a radial scaling function and a radial wavelet from an even classical scaling function on {\bf R}. Furthermore, decomposition and reconstruction algorithms are formulated.  相似文献   

2.
We study the random variables of radial asymmetry based on copulas. We research on the structure of random variables which radial asymmetry degree isand get the exact best-possible bounds of random variables which radial asymmetry degree is equal to. Then we expand to general case. We propose an essential condition of radial asymmetry degree is and study the structure of copula. We provide a broad bounds of copula that the radial asymmetry degree is .  相似文献   

3.
In this paper,we investigate the radial function manifolds generated by a linear combination of radial functions.Let Wpr(Bd) be the usual Sobolev class of functions on the unit ball B d.We study the deviation from the radial function manifolds to Wpr(Bd).Our results show that the upper and lower bounds of approximation by a linear combination of radial functions are asymptotically identical.We also find that the radial function manifolds and ridge function manifolds generated by a linear combination of ridg...  相似文献   

4.
Lutwak showed the radial bodies combining with the radial Minkowski linear combinations of star bodies. In this paper, the general radial bodies are introduced and its some properties and inequalities are established.  相似文献   

5.
《数学季刊》2016,(2):171-177
Lutwak showed the radial bodies combining with the radial Minkowski linear combinations of star bodies. In this paper, the general radial bodies are introduced and its some properties and inequalities are established.  相似文献   

6.
In local radial gravitational force fields there is no viable flow of the force itself, and if divergence of a vector is constructed within the field, then it actually requires time-based radial gravitational potentials rather than the usual distance-based radial potentials. When cast in structural relationships of multispatial hyperspace, the new multispatial representation of the usual, Newtonian radial gravity term suggests thus that the allegedly missing mass-energy of the known universe may be the result of inappropriate accounting methods rather than cosmic mass deficiency, as some used to believe. More detailed analysis of local radial gravitational field reveals that the allegedly universal gravitational constant hides fairly compound functional of locally constant value and therefore the radial force depends on more variables than are explicitly displayed in the Newton's inverse square law of gravitation.  相似文献   

7.
Li  Ran  Lu  Yu Feng 《数学学报(英文版)》2019,35(2):227-238
In this paper, we study radial operators in Toeplitz algebra on the weighted Bergman spaces over the polydisk by the(m, λ)-Berezin transform and find that a radial operator can be approximated in norm by Toeplitz operators without any conditions. We prove that the compactness of a radial operator is equivalent to the property of vanishing of its(0, λ)-Berezin transform on the boundary. In addition, we show that an operator S is radial if and only if its(m, λ)-Berezin transform is a separately radial function.  相似文献   

8.
赵霞  王卫东 《数学学报》1936,63(4):409-416
2006年,Schuster提出了径向Blaschke-Minkowski同态的概念.随后,汪卫等人将其推广到Lp径向Blaschke-Minkowski同态.本文结合Lp对偶几何表面积,建立了Lp径向Blaschke-Minkowski同态的若干不等式,包括Brunn-Minkowski型不等式和单调不等式.并给出了Lp径向Blaschke-Minkowski同态的Busemann-Petty问题的肯定和否定形式.  相似文献   

9.
In this paper, we consider multivariate interpolation with radial basis functions of finite smoothness. In particular, we show that interpolants by radial basis functions in ℝ d with finite smoothness of even order converge to a polyharmonic spline interpolant as the scale parameter of the radial basis functions goes to zero, i.e., the radial basis functions become increasingly flat.  相似文献   

10.
The convergence for the radial minimizers of a second-order energy functional, when the parameter tends to 0 is studied. And the location of the zeros of the radial minimizers of this functional is presented. Based on this result, the uniqueness of the radial minimizer is discussed.  相似文献   

11.
本文证明了凸体的p次径向平均体的线性不变性和椭球的p次径向平均体仍是椭球,并且获得了p次径向平均体相应于Blaschke-Santaló不等式的一个反向不等式.  相似文献   

12.
We prove some new Strichartz estimates for a class of dispersive equations with radial initial data. In particular, we obtain the full radial Strichartz estimates up to some endpoints for the Schrödinger equation. Using these estimates, we obtain some new results related to nonlinear problems, including small data scattering and large data LWP for the nonlinear Schrödinger and wave equations with radial critical initial data and the well-posedness theory for the fractional order Schrödinger equation in the radial case.  相似文献   

13.
函数的径向基表示   总被引:16,自引:0,他引:16  
吴宗敏 《数学进展》1998,27(3):202-208
本文是关于函数的径向表示的综述性文章,基于我们对这方面的研究工作的了解,介绍了国际上近年来这方面的主要的有关研究结果以及在一些领域中应用的情况,文后附有主要的参考文献以便感兴趣的读者查阅。  相似文献   

14.
不可压缩层合橡胶圆管径向膨胀的稳定性分析   总被引:1,自引:0,他引:1       下载免费PDF全文
研究由两类不可压缩的橡胶材料组成的层合圆柱形管道,在内表面受到突加的径向压力作用时的膨胀机理.建立了问题的数学模型;利用材料的不可压缩条件、边界条件以及圆管的径向位移和径向应力的连续性条件将相应的控制方程约化为一个二阶非线性常微分方程,并得到了该方程的首次积分.给出了管道拟静态膨胀和动态膨胀的定性分析,特别地,结合数值算例讨论了材料参数、结构参数以及径向压力对管道径向膨胀和非线性周期振动的影响.  相似文献   

15.
Construction of global optimization algorithms using statistical models and radial basis function models is discussed. A new method of data smoothing using radial basis function and least squares approach is presented. It is shown that the P-algorithm for global optimization in the presence of noise based on a statistical model coincides with the corresponding radial basis algorithm.  相似文献   

16.
引进了一种新的二阶组合切锥, 利用它引进了一种新的二阶组合切导数, 称为二阶组合径向切导数, 并讨论了它的性质及它与二阶组合切导数的关系, 借助二阶径向组合切导数, 分别建立了集值优化取得Benson真有效元的最优性充分和必要条件.  相似文献   

17.
In this paper, the problem of solving the one-dimensional parabolic partial differential equation subject to given initial and non-local boundary conditions is considered. The approximate solution is found using the radial basis functions collocation method. There are some difficulties in computing the solution of the time dependent partial differential equations using radial basis functions. If time and space are discretized using radial basis functions, the resulted coefficient matrix will be very ill-conditioned and so the corresponding linear system cannot be solved easily. As an alternative method for solution, we can use finite-difference methods for discretization of time and radial basis functions for discretization of space. Although this method is easy to use but an accurate solution cannot be provided. In this work an efficient collocation method is proposed for solving non-local parabolic partial differential equations using radial basis functions. Numerical results are presented and are compared with some existing methods.  相似文献   

18.
In this paper we investigate existence and uniqueness of radial graphs ofconstant mean curvature (cmc) with prescribed boundary. Our main resultestablishes the existence of a minimal radial anullus spanning two givenconvex curves in parallel planes of R3; we also obtain a variant ofa well-known result of James Serrin about the existence of radial cmc graphsover convex domains in the sphere.  相似文献   

19.
In the setting of the Fock space over the complex plane, Bauer and Lee have recently characterized commutants of Toeplitz operators with radial symbols, under the assumption that symbols have at most polynomial growth at infinity. Their characterization states: If one of the symbols of two commuting Toeplitz operators is nonconstant and radial, then the other must be also radial. We extend this result to the Fock–Sobolev spaces.  相似文献   

20.
基于材料体积不可压假设,对轴向压缩作用下圆柱试件在加载面内的环向和径向应力分布进行理论分析,计算结果表明:当试件材料本构为正交各向异性时,环向和径向应力分布为半径的幂函数形式;试件材料为横观各向同性时,环向和径向应力为半径的二次函数.在圆柱试件轴线上环向和径向应力相等,且均具有最大值;试件圆周边界上径向应力为0,环向应力具有极小值.通过最大拉伸应变破坏理论对试件环向应变进行分析,获得了产生环向拉伸破坏时的临界轴向载荷;并采用Hill-蔡强度理论对试件圆周边界上计算得到的应力参量进行描述,得到了轴压作用下圆柱试件的Hill-蔡强度理论表达式,其不仅取决于轴向应力和试件材料的基本力学性能,还与试件轴向变形的应变率及应变率随时间的变化率相关.  相似文献   

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