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91.
In this paper, Hopf bifurcation of the third-order Hénon system is studied via a simple explicit criterion, which is derived from the Schur–Cohn Criterion. Moreover stability of Hopf bifurcation is also investigated by using the normal form method and center manifold theory for the discrete time system developed by Kuznetsov. Test results containing simulations and circuit measurement are shown to demonstrate that the criterion is correct and feasible. 相似文献
92.
We consider strongly monotone continuous planar vector fields with a finite number of fixed points. The fixed points fall into three classes, attractors, repellers and saddles. Naturally, the relative positions of the fixed points must obey a set of restrictions imposed by monotonicity. The study of these restrictions is the main goal of the paper. With any given vector field, we associate a matrix describing the arrangement of the fixed points on the plane. We then use these matrices to formulate simple necessary and sufficient conditions which allow one to determine whether a finite set of attractors, repellers and saddles at given positions on the plane can be realized as the fixed point set of a strongly monotone vector field. 相似文献
93.
设■:D→R~3确定了以等温参数表示的极小曲面M,其中D是全平面R~2的开子区域,那么极小曲面的Gauss映射g(z)是D上的亚纯函数.Xavier与Chao提出了一个尚未解决的问题:任意给定区域■上的亚纯函数g(z),它是否是某完备极小曲面的Gauss映射?本文证明了若开平面C上的亚纯函数g(z)的零点列或极点列的收敛指数小于1/2,则g(z)—定是某完备极小曲面的Gauss映射. 相似文献
94.
Alexander Belyaev 《Journal of Difference Equations and Applications》2019,25(9-10):1468-1487
ABSTRACTWe consider a one-dimensional model of neural activity, given by a piecewise smooth discontinuous map. Fold bifurcations as well as border collision bifurcations are described in detail. Using the method of stochastic sensitivity functions, noise-induced phenomena, such as transitions within attractor and between attractors, and spike generation, are described. Statistical characteristics of interspike intervals depending on noise intensity are studied. 相似文献
95.
In this paper, based on the smooth point of the unit ball and its support linear functional,we show two equivalent formulations of the isometric extension problem between the unit spheres of strictly convex two-dimensional normed spaces. We prove that these equivalent formulations have a positive answer in a special case. 相似文献
96.
97.
We study bifurcations of two-dimensional symplectic maps with quadratic homoclinic tangencies and prove results on the existence
of cascade of elliptic periodic points for one and two parameter general unfoldings.
相似文献
98.
The set of 16 polycyclic aromatic hydrocarbon compounds was examined with the Internet available quantitative structure–activity relationship (QSAR) CAESAR models. For mutagenicity, carcinogenicity, developmental toxicity, and skin sensitization, the report includes the predicted classifications, the analysis of applicability domains, and the similarity sets, which consist of the similar compounds from the training sets. These results were further analyzed with chemometrical methods, that is, hierarchical clustering, principal component analysis, and self‐organizing maps, which were used for clustering and to define the cluster indicators. Such analysis assists the users in planning the application of QSAR models for hazard communication in regulatory compliance and in research of new active compounds. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
99.
Patterns were generated inside a horizontal cylinder rotating at low speeds. The cylinder was filled with a very low volume liquid fraction of 1.8% of Newtonian fluid and the rotation speed ranged between 0.08 and 5.2 s−1. A novel laser-plane technique was utilized to obtain time series from each pattern. This enabled the characterization of fluid patterns using Fourier spectral (FS) and dynamical-systems (chaotic) techniques such as the recurrence map, correlation dimension (D2) and Hurst exponent (H). Four patterns were found (fingers, furrows, waterfall and smooth tooth) before annular flow was reached. The results indicate that the FS technique not is suitable for flow pattern characterization; and H only has the ability to indicate a possible pattern change. The best tool for indicating the pattern transitions and the inner coat liquid evolution was found to be recurrence maps and D2. 相似文献
100.
Jonathan Spreer 《Discrete Mathematics》2011,(14):1295
We investigate slicings of combinatorial manifolds as properly embedded co-dimension 1 submanifolds. Focus is given to the case of dimension 3, where slicings are (discrete) normal surfaces. For the cases of 2-neighborly 3-manifolds as well as quadrangulated slicings, lower bounds on the number of quadrilaterals of slicings depending on its genus g are presented. These are shown to be sharp for infinitely many values of g. Furthermore, we classify slicings of combinatorial 3-manifolds which are weakly neighborly polyhedral maps. 相似文献