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141.
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143.
It is proposed in this paper to use the generalized cell mapping to locate strange attractors of dynamical systems and to determine their statistical properties. The cell-to-cell mapping method is based upon the idea of replacing the state space continuum by a large collection of state space cells and of expressing the evolution of the dynamical system in terms of a cell-to-cell mapping. This leads to a Markov chain which in turn allows us to compute all the statistical properties as well as the invariant distribution. After a general discussion, the method is applied in this paper to strange attractors of a variety of systems governed either by point mappings or by differential equations. The results indicate that it is a viable, effective and attractive method. Some comments on this method in comparison with the method of direct iteration will also be made. 相似文献
144.
We show that a discrete, quasiconformal group preserving
n
has the property that its exponent of convergence and the Hausdorff dimension of its limit set detect the existence of a non-empty regular set on the sphere at infinity to
n
. This generalizes a result due separately to Sullivan and Tukia, in which it is further assumed that the group act isometrically on
n
, i.e. is a Kleinian group. From this generalization we are able to extract geometric information about infinite-index subgroups within certain of these groups. 相似文献
145.
在C~n中有界凸Reinhardt域上讨论了一类介于凸映射类与星形映射类之间的“完全准凸映射类”.特别地,在C~n中的多圆柱上给出了完全准凸映射的分解定理,得到了多圆柱上判别凸映射的一个改进的充分条件. 相似文献
146.
Xuan-weiZhou Yu-daHu 《应用数学学报(英文版)》2004,20(2):309-316
This paper deals with the connectedness of the cone-efficient solution set for vector optimization inlocally convex Hausdorff topological vector spaces.The connectedness of the cone-efficient solution set is provedfor multiobjective programming defined by a continuous cone-quasiconvex mapping on a compact convex set ofalternatives.The generalized saddle theorem plays a key role in the proof. 相似文献
147.
Guowu Yao 《Proceedings of the American Mathematical Society》2004,132(8):2483-2493
Let be a sequence of locally quasiconformal harmonic maps on the unit disk with respect to the Poincaré metric. Suppose that the energy densities of are uniformly bounded from below by a positive constant and locally uniformly bounded from above. Then there is a subsequence of that locally uniformly converges on , and the limit function is either a locally quasiconformal harmonic map of the Poincaré disk or a constant. Especially, if the limit function is not a constant, the subsequence can be chosen to satisfy some stronger conditions. As an application, it is proved that every point of the space , a subspace of the universal Teichmüller space, can be represented by a quasiconformal harmonic map that is an asymptotic hyperbolic isometry.
148.
For any subset A of the unit sphere of a Banach space X and for [0,2) the notion of -flatness is introduced as a measure of non-flatness of A. For any positive , construction of locally finite tilings of the unit sphere by -flat sets is carried out under suitable -renormings of X in a quite general context; moreover, a characterization of spaces having separable dual is provided in terms of the existence of such tilings. Finally, relationships between the possibility of getting such tilings of the unit sphere in the given norm and smoothness properties of the norm are discussed. 相似文献
149.
Ha|YunZHOU 《数学学报(英文版)》2004,20(5):829-836
In this article, we will investigate the properties of iterative sequence for non-expansive mappings and present several strong and weak convergence results of successive approximations to fixed points of non-expansive mappings in uniformly convex Banach spaces. The results presented in this article generalize and improve various ones concerned with constructive techniques for the fixed points of non-expansive mappings. 相似文献
150.
. Kancleris A. Laurinaviius T. Anbinderis 《International Journal of Infrared and Millimeter Waves》2004,25(7):1099-1108
A plane electromagnetic wave normally falling on a surface of a dielectric plate has been considered to investigate the sensitivity of the dielectric constant homogeneity mapping in the dielectric wafer by measuring the phase and/or the amplitude of the millimeter wave reflected from or transmitted through it. Measurement conditions at which the highest sensitivity might be achieved are established. The sensitivity at Fabry-Perot resonance conditions as well as at frequency shifted from resonance has been considered. 相似文献