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101.
In this paper, we treat an inverse problem for a radially symmetric heat equation, which arises from non-destructive evaluation by thermal imaging. The problem can also be considered as an inverse heat conduction problem. Based on a weighted energy method, we give a conditional stability estimate. A feasible regularization method is provided for numerical simulation. The reconstruction experiment is done for verifying the efficiency of the regularization method. 相似文献
102.
流固耦合介质轴对称动力问题解法的改进 总被引:7,自引:0,他引:7
用直接求解常微分方程组解文[1]所得的控制方程,减少了传递矩阵计算工作量,避免了子阵求逆,使问题的求解得到了简化 相似文献
103.
完全刻画多重调和Bergman空间上Toeplitz算子和Hankel算子的紧性.运用紧Toeplitz算子这个结果,建立了Toeplitz代数和小Hankel代数的短正合列,推广了单位圆盘上相应的结果. 相似文献
104.
采用Hankel变换分析半空间受扭矩作用时的响应。在获得应力和位移通式的基础上,讨论了集中扭矩作用下轴弹性和正交异性半空间问题,给出了位移和应力的解析表达. 相似文献
105.
Jianping Gu Xiaohan Sun Mingde Zhang 《International Journal of Infrared and Millimeter Waves》2002,23(2):317-324
A novel and numerically efficient treatment of electromagnetic modes localized at defects in two-dimension (2D) photonic crystals is presented in this paper. The method represents the fields in terms of scattered fields by each column of the photonic crystals. With the method, the field distributions in two photonic crystal structures are calculated with satisfying results. 相似文献
106.
We develop fixed-point algorithms for the approximation of structured matrices with rank penalties. In particular we use these fixed-point algorithms for making approximations by sums of exponentials, i.e., frequency estimation. For the basic formulation of the fixed-point algorithm we show that it converges to the solution of a related minimization problem, namely the one obtained by replacing the original objective function with its convex envelope and keeping the structured matrix constraint unchanged.It often happens that this solution agrees with the solution to the original minimization problem, and we provide a simple criterion for when this is true. We also provide more general fixed-point algorithms that can be used to treat the problems of making weighted approximations by sums of exponentials given equally or unequally spaced sampling. We apply the method to the case of missing data, although the above mentioned convergence results do not hold in this case. However, it turns out that the method often gives perfect reconstruction (up to machine precision) in such cases. We also discuss multidimensional extensions, and illustrate how the proposed algorithms can be used to recover sums of exponentials in several variables, but when samples are available only along a curve. 相似文献
107.
A Toeplitz determinant whose entries are described by a q-analogue of the Narayana polynomials is evaluated by means of Laurent biorthogonal polynomials which allow of a combinatorial interpretation in terms of Schröder paths. As an application, a new proof is given to the Aztec diamond theorem by Elkies, Kuperberg, Larsen and Propp concerning domino tilings of the Aztec diamonds. The proof is based on the correspondence with non-intersecting Schröder paths developed by Johansson. 相似文献
108.
PengYanHU WenJunZHANG 《数学学报(英文版)》2004,20(2):261-272
In this paper the small Hankel operators on the Dirichlet-type spaces Dp on the unit ball of C^n are considered. A similar result to that of the one-dimensional setting is given, which characterizes the boundedness of the small Hankel operators on Dp. 相似文献
109.
Let the real functionsK(x) andL(x) be such thatM(x)=K(x)+iL(x)=eix
g(x), whereg(x) is infinitely differentiable for all largex and is non-oscillatory at infinity. We develop an efficient automatic quadrature procedure for numerically computing the integrals
a
K(t)f(t) and
a
L(t)f(t)dt, where the functionf(t) is smooth and nonoscillatory at infinity. One such example for which we also provide numerical results is that for whichK(x)=J
(x) andL(x)=Y
(x), whereJ
(x) andY
(x) are the Bessel functions of order . The procedure involves the use of an automatic scheme for Fourier integrals and the modified W-transformation which is used for computing oscillatory infinite integrals. 相似文献
110.
S. K. Upadhyay 《Applicable analysis》2013,92(4):415-428
Lp-norm type inequalities for pseudo-differential operators L(x,D) and H(x,D) are derived for 1 ≤ p < ∞. Product of pseudo-differential operators associated with Bessel operator Sμ are defined and its Lp-norm type inequalities are obtained. 相似文献