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991.
THE VARIATION OF INVARIANT LINES AND LIMIT CYCLES FOR A QUADRATIC DIFFERENTIAL SYSTEM 总被引:1,自引:0,他引:1
1IntroductionConsidertherealquadraticdiferentialsystemx=-y+δx-4x2+3xy+13y2y=x(1-13x-y).(1)First,forconvenience,wedenotethetwo... 相似文献
992.
本文提出并研究下列四类线性预测问题:2(n0),6(n0),5(NO,n0)及3(N0,n0).不仅求出了它们的预测误差,而且也求出了它们的预测值.因而不仅推广了而且也改进了[2-5]中的结果.本文还给出了场{X(m,n)}的一个新形式的表示式. 相似文献
993.
A learning process for fuzzy control rules using genetic algorithms 总被引:10,自引:0,他引:10
The purpose of this paper is to present a genetic learning process for learning fuzzy control rules from examples. It is developed in three stages: the first one is a fuzzy rule genetic generating process based on a rule learning iterative approach, the second one combines two kinds of rules, experts rules if there are and the previously generated fuzzy control rules, removing the redundant fuzzy rules, and the thrid one is a tuning process for adjusting the membership functions of the fuzzy rules. The three components of the learning process are developed formulating suitable genetic algorithms. 相似文献
994.
B. Mansouri N. Manamanni K. Guelton M. Djemai 《Nonlinear Analysis: Hybrid Systems》2008,2(4):1136-1143
This paper concerns the state feedback control for continuous-time, disturbed and uncertain linear switched systems with arbitrary switching rules. The main result of this work consists in getting a LMI (Linear Matrix Inequalities) condition guaranteeing a robust pole placement according to some desired specifications. Then, external disturbance attenuation with a fixed rate according to the H∞ criterion is ensured. This is obtained thanks to the existence of a common quadratic Lyapunov function for all sub-systems. Finally, an academic example illustrates the efficiency of the developed approach. 相似文献
995.
Hong-Wei Ge Feng Qian Yan-Chun Liang Wen-li Du Lu Wang 《Nonlinear Analysis: Real World Applications》2008,9(4):1345-1360
In this paper, we first present a learning algorithm for dynamic recurrent Elman neural networks based on a dissimilation particle swarm optimization. The proposed algorithm computes concurrently both the evolution of network structure, weights, initial inputs of the context units, and self-feedback coefficient of the modified Elman network. Thereafter, we introduce and discuss a novel control method based on the proposed algorithm. More specifically, a dynamic identifier is constructed to perform speed identification and a controller is designed to perform speed control for Ultrasonic Motors (USM). Numerical experiments show that the novel identifier and controller based on the proposed algorithm can both achieve higher convergence precision and speed than other state-of-the-art algorithms. In particular, our experiments show that the identifier can approximate the USM's nonlinear input–output mapping accurately. The effectiveness of the controller is verified using different kinds of speeds of constant, step, and sinusoidal types. Besides, a preliminary examination on a randomly perturbation also shows the robust characteristics of the two proposed models. 相似文献
996.
In this paper, we propose a sinusoidal phase modulating (SPM) interferometer that is insensitive to external disturbances, and its measuring principle is analyzed theoretically. In the SPM interferometer, the interference signal is detected by a high-speed image sensor based on a low-speed CCD and a signal processing circuit is used to obtain the phase of each point on the surface. Therefore, the surface profile can be measured real-time. The experiments measuring the surface profile of a wedge-shaped optical flat show that the measurement time of the SPM interferometer is less than 10 ms, the repetitive measurement accuracy is 4.2 nm. The results show that the impacts of nonlinear distortion of the piezoelectric transducer (PZT) and part external disturbance are removed. 相似文献
997.
In 1991, one of the authors showed the existence of quadratic transformations between the Painlevé VI equations with local monodromy differences (1/2, a, b, ±1/2) and (a, a, b, b). In the present paper we give concise forms of these transformations. They are related to the quadratic transformations obtained by Manin and Ramani–Grammaticos–Tamizhmani via Okamoto transformations. To avoid cumbersome expressions with differentiation, we use contiguous relations instead of the Okamoto transformations. The 1991 transformation is particularly important as it can be realized as a quadratic‐pull back transformation of isomonodromic Fuchsian equations. The new formulas are illustrated by derivation of explicit expressions for several complicated algebraic Painlevé VI functions. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
998.
The main goals of this paper are to: i) relate two iteration-complexity bounds derived for the Mizuno-Todd-Ye predictor-corrector
(MTY P-C) algorithm for linear programming (LP), and; ii) study the geometrical structure of the LP central path. The first
iteration-complexity bound for the MTY P-C algorithm considered in this paper is expressed in terms of the integral of a certain
curvature function over the traversed portion of the central path. The second iteration-complexity bound, derived recently
by the authors using the notion of crossover events introduced by Vavasis and Ye, is expressed in terms of a scale-invariant
condition number associated with m × n constraint matrix of the LP. In this paper, we establish a relationship between these bounds by showing that the first one
can be majorized by the second one. We also establish a geometric result about the central path which gives a rigorous justification
based on the curvature of the central path of a claim made by Vavasis and Ye, in view of the behavior of their layered least
squares path following LP method, that the central path consists of long but straight continuous parts while the remaining curved part is relatively “short”.
R. D. C. Monteiro was supported in part by NSF Grants CCR-0203113 and CCF-0430644 and ONR grant N00014-05-1-0183. T. Tsuchiya
was supported in part by Japan-US Joint Research Projects of Japan Society for the Promotion of Science “Algorithms for linear
programs over symmetric cones” and the Grants-in-Aid for Scientific Research (C) 15510144 of Japan Society for the Promotion
of Science. 相似文献
999.
一类非线性时滞系统与时滞相关的H_∞控制 总被引:1,自引:0,他引:1
辛云冰 《数学的实践与认识》2008,38(18)
考虑一类非线性时滞系统的H∞控制.并对非线性项给出了一个新假设,在其假设下利用线性矩阵不等式方法得到了与时滞相关的H∞控制,同时也得到了该类非线性时滞系统鲁棒镇定的充分条件. 相似文献
1000.