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171.
172.
Barbara Panicucci Massimo Pappalardo Mauro Passacantando 《Computational Optimization and Applications》2009,43(2):197-211
We propose a descent method via gap functions for solving nonsmooth variational inequalities with a locally Lipschitz operator.
Assuming monotone operator (not necessarily strongly monotone) and bounded domain, we show that the method with an Armijo-type
line search is globally convergent. Finally, we report some numerical experiments.
This work has been supported by the National Research Program PRIN/2005017083 “Innovative Problems and Methods in Nonlinear
Optimization”. 相似文献
173.
174.
主要讨论作用在复Hilbert空间弱闭 AlgN-模上的线性保秩映射,并给出在各种情况下保秩一性线性映射的刻画.作为应用,最后讨论了弱闭 AlgN-模上的模同构,并得出这样的同构是平凡的. 相似文献
175.
Miklós Hoffmann 《Numerical Algorithms》2005,39(1-3):175-186
Surface reconstruction from scattered data using Kohonen neural network is presented in this paper. The network produces a topologically predefined grid from the unordered data which can be applied as a rough approximation of the input set or as a base surface for further process. The quality and computing time of the approximation can be controlled by numerical parameters. As a further application, ruled surface is produced from a set of unordered lines by the network.
AMS subject classification 68U07, 65D17, 68T20 相似文献
176.
本文的主要结论是给出了一个更广泛形式的Mazur-Ulam定理.讨论的对象是实的赋准范空间,满等距算子被减弱成其像空间构成一个加法子群的算子.最后给出的推论推广了Skof的一个结果. 相似文献
177.
The authors obtain a holomorphic Lefschetz fixed point formula for certain non-compact “hyperbolic” K¨ahler manifolds (e.g. K¨ahler hyperbolic manifolds, bounded domains of holomorphy) by using the Bergman kernel. This result generalizes the early work of Donnelly and Fefferman. 相似文献
178.
We propose a new method for image encryption using fractional Fourier transform and chaos theory. Random phase masks are generated using iterative chaos functions. The input image is combined with the first random phase mask at the object plane and is then transformed using the fractional Fourier transform. After the first fractional Fourier transform, the second random phase mask, again generated by using the chaos functions, is used at the fractional plane. The second fractional Fourier transform operation is then carried out to obtain the encrypted image. Three types of chaos functions have been used: the logistic map, the tent map and the Kaplan–Yorke map. The mean square error and the signal-to-noise ratio between the decrypted image and the input image for the correct order and the incorrect order of the fractional Fourier transform have been calculated. The computer simulations are presented to verify the validity of the proposed technique. 相似文献
179.
OBUL Abdukadir College of Mathematics System Sciences Xinjiang University Urumqi China PANG YaLi 《中国科学A辑(英文版)》2008,(6)
By using Frobenius maps and F-stable representations,we count the number of isomor- phism classes of indecomposable representations with the fixed dimension vector of a species of type _n over a finite field,first,and then,as an application,give a q-analogue of the Weyl-Kac denominator identity of type _n. 相似文献
180.
Poincaré maps have been proved to be a valuable tool in the analysis of non-linear dynamical systems, which usually reduce a continuous phase flow into a two-dimensional discrete map. However, they may be inconvenient for reflecting some characteristics of the system response. In this paper, two novel methods, using the period sampling peak-to-peak value (PSP) diagram and the modified Poincaré map, are presented for characterizing different types of non-linear response. These two methods take advantage of some parameters of the response, such as the peak-to-peak value within an exterior excitation period and the mean value of the displacement. In the PSP diagram method, a two-dimensional graph is plotted by taking the peak-to-peak value as ordinate and the sequential periodically sampling number as abscissa. On the other hand, the modified Poincaré map takes the mean value of the velocity within an exterior excitation period as ordinate and the relevant mean value of the displacement as abscissa. The non-linear responses of a Duffing system, a pendulum with circular motion support and an oscillating circuit are studied by these methods. We also studied the intermittent chaos of the Lorenz system by the PSP diagram method. The PSP diagram is a set of mapping points, which form: a straight line for a one-period response; multi-straight lines for a multi-period response; orderly periodic curves for a quasi-period response; long lines interrupted by transitoriness confusion points for intermittent chaos; and totally out-of-order points for chaos. The figures for the modified Poincaré maps for the period, multi-period, quasi-period responses and chaos are almost identical to those for the Poincaré maps, but the modified maps take more sampling points and can reflect the mean values of the responses. Some numerical results are given based on these methods to show their efficiency in distinguishing different non-linear responses. 相似文献