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81.
L-曲线估计确定正则参数的双网格迭代法 总被引:1,自引:0,他引:1
本文考虑对不适定问题离散化得到的大规模不适定线性方程组进行Tiknonov正则化,然后用双网格迭代法求解得到的Tikhonov正则化方程组,并用L-曲线估计法来确定正则参数.试验问题的数值结果表明双网格迭代法求解正则化后的对称正定线性方程组效果很好,且L-曲线估计法确定正则参数计算量很小. 相似文献
82.
On the embedding of variational inequalities 总被引:1,自引:0,他引:1
B. Djafari Rouhani A. A. Khan 《Proceedings of the American Mathematical Society》2003,131(12):3861-3871
This work is devoted to the approximation of variational inequalities with pseudo-monotone operators. A variational inequality, considered in an arbitrary real Banach space, is first embedded into a reflexive Banach space by means of linear continuous mappings. Then a strongly convergent approximation procedure is designed by regularizing the embedded variational inequality. Some special cases have also been discussed.
83.
Gottfried Bruckner Johannes Elschner 《Mathematical Methods in the Applied Sciences》2005,28(7):757-778
We consider the inverse problem of recovering a 2D periodic structure from scattered waves measured above and below the structure. We discuss convergence and implementation of an optimization method for solving the inverse TE transmission problem, following an approach first developed by Kirsch and Kress for acoustic obstacle scattering. The convergence analysis includes the case of Lipschitz grating profiles and relies on variational methods and solvability properties of periodic boundary integral equations. Numerical results for exact and noisy data demonstrate the practicability of the inversion algorithm. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
84.
85.
C. C. Agunwamba 《Mathematical Programming》1977,13(1):38-48
Necessity and sufficiency conditions are given for the existence of a finite set of redundant constraints which together with a given set of constraints in an optimization problem satisfy the Kuhn—Tucker, and the Guignard Constraint qualifications when the original set of constraints fails to satisfy either or both of them.This work was carried out at the Department of Statistics, University College of Wales, Aberystwyth while the author was sponsored by the Commonwealth Scholarship Commission in the United Kingdom, through the Department of Statistics, University of Nigeria, Nsukka. 相似文献
86.
We introduce a generalized notion of the zeta regularization. As applications we show the quantum analogue of the Lerch formula
and of the Dirichlet class number formulas. We also give some further examples related to Appell's O-functions.
2000 Mathematics Subject Classification: Primary—11M36
Work in part supported by Grant-in Aid for Scientific Research (B) No. 11440010, and by Grant-in Aid for Exploratory Research
No. 13874004, Japan Society for the Promotion of Science. 相似文献
87.
F. De Vylder 《Insurance: Mathematics and Economics》1983,2(3):139-145
Let Lj (j = 1, …, n + 1) be real linear functions on the convex set of probability distributions. We consider the problem of maximization of Ln+1(F) under the constraint F ? and the equality constraints L1(F) = z1 (i = 1, …, n). Incorporating some of the equality constraints into the basic set , the problem is equivalent to a problem with less equality constraints. We also show how the dual problems can be eliminated from the statement of the main theorems and we give a new illuminating proof of the existence of particular solutions.The linearity of the functions Lj(j = 1, …, n + 1) can be dropped in several results. 相似文献
88.
89.
We present an ultra compact and high resolution free space optical spectrometer and demonstrate it by using FDTD simulations. The miniature interferometer-based speetrometer is a series of submicron phase objects on a polymethyl methacrylate(PMMA) film with a CCD as the detector. The speetrum is obtained by solving a system of simultaneous linear equations. The Tikhonov regularization method is used to achieve a resolution at the picometer level. Compared with conventional speetrometers, the proposed device is low-cost and easy to fabricate due to its simple structure. Furthermore, its compact feature renders the device ideal for miniaturization and integration as the systems in microfluidics architectures and lab-on-chip designs. 相似文献
90.
Adrian Doicu Olena Schüssler Diego Loyola 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(6):907-916
In this paper we present several constrained regularization methods for ozone profile retrieval from UV/VIS nadir sounding instruments such as GOME, SCIAMACHY, OMI and GOME-2. These methods extend the Tikhonov regularization and the iteratively regularized Gauss-Newton method with equality and inequality constraints imposed on the vertical column. It will be shown that this type of information, which is delivered by an independent algorithm like DOAS or GODFIT, significantly improves the accuracy and stability of the profile retrieval. 相似文献