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1.
关于迭代Tikhonov正则化的最优正则参数选取 总被引:2,自引:0,他引:2
本文讨论了算子和右端都近似给定的第一类算子方程的迭代Tikhonov正则化,给出了不依赖于准确解的任何信息但能得到最优收敛阶的正则参数选取法。 相似文献
2.
周奇年 《原子与分子物理学报》1997,14(2):260-263
阐述了计算机科学对原子分子学科研究的重要作用,针对原子与分子领域中一些典型的问题,介绍了计算方法及程序设计,并对有关课题编出了计算程序。从而表明:借助于计算机可使原子与分子研究工作规范化、工程化,计算机及其程序设计是原子分子工程的设计基础 相似文献
3.
After an introduction to interstitial incorporation of 2p elements in iron-based alloys, the main physical effects of these interstitials on the intrinsic properties of rare-earth intermetallics are outlined. Then follows a survey of the results obtained using the57Fe and several rare-earth resonances for rare-earth intermetallics with the Th2Zn17, Th2Ni17, ThMn12 and BaCd11 structures in which nitrogen or carbon has been interstitially incorporated. The results of Mössbauer studies in this area are discussed, and future prospects are assessed. 相似文献
4.
Leithe-Jasper A. Weitzer F. Rogl P. Qi Qinian Coey J. M. D. 《Hyperfine Interactions》1994,94(1):2327-2332
The ternary stannide series of RMnSn2 compounds crystallize in the defect orthorhombic CeNiSi2-type structure. They order magnetically close to room temperature. Isomer shifts are approximately 1.9 and 2.8 mm/s at the two tin sites, and there are transferred hyperfine fields of 3–6 T at 15 K, which depend on the rare-earth partner, especially at Sn2 sites. The magnitude of the transferred hyperfine field per manganese neighbour is 4T. 相似文献
5.
Qinian Jin 《Applicable analysis》2013,92(3):527-548
In this article, we solve nonlinear inverse problems by an evolution equation method which can be viewed as the continuous analogue of the Gauss–Newton method. Under certain conditions we prove the convergence and derive the rate of convergence when the discrepancy principle is coupled. 相似文献
6.
Qinian Jin 《Numerische Mathematik》2010,115(2):229-259
We consider a regularized Levenberg–Marquardt method for solving nonlinear ill-posed inverse problems. We use the discrepancy
principle to terminate the iteration. Under certain conditions, we prove the convergence of the method and obtain the order
optimal convergence rates when the exact solution satisfies suitable source-wise representations. 相似文献
7.
8.
In this paper we propose an extension of the iteratively regularized Gauss–Newton method to the Banach space setting by defining the iterates via convex optimization problems. We consider some a posteriori stopping rules to terminate the iteration and present the detailed convergence analysis. The remarkable point is that in each convex optimization problem we allow non-smooth penalty terms including $L^1$ and total variation like penalty functionals. This enables us to reconstruct special features of solutions such as sparsity and discontinuities in practical applications. Some numerical experiments on parameter identification in partial differential equations are reported to test the performance of our method. 相似文献
9.
Qinian Jin 《Numerische Mathematik》2012,121(2):237-260
Inexact Newton regularization methods have been proposed by Hanke and Rieder for solving nonlinear ill-posed inverse problems. Every such a method consists of two components: an outer Newton iteration and an inner scheme providing increments by regularizing local linearized equations. The method is terminated by a discrepancy principle. In this paper we consider the inexact Newton regularization methods with the inner scheme defined by Landweber iteration, the implicit iteration, the asymptotic regularization and Tikhonov regularization. Under certain conditions we obtain the order optimal convergence rate result which improves the suboptimal one of Rieder. We in fact obtain a more general order optimality result by considering these inexact Newton methods in Hilbert scales. 相似文献
10.
We consider the computation of stable approximations to the exact solution of nonlinear ill-posed inverse problems F(x) = y with nonlinear operators F : X → Y between two Hilbert spaces X and Y by the Newton type methods
in the case that only available data is a noise of y satisfying with a given small noise level . We terminate the iteration by the discrepancy principle in which the stopping index is determined as the first integer such that
with a given number τ > 1. Under certain conditions on {α
k
}, {g
α
} and F, we prove that converges to as and establish various order optimal convergence rate results. It is remarkable that we even can show the order optimality
under merely the Lipschitz condition on the Fréchet derivative F′ of F if is smooth enough. 相似文献