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111.
In this paper, the output feedback control of uncertain chaotic systems is addressed via an adaptive robust fuzzy approach.
Fuzzy logic systems are employed to approximate uncertain nonlinear functions in the chaotic systems. Because only partial
information of the system’s states is needed to be known, an observer is given to estimate the unmeasured states. Compared
with the existing results in the observer design, the prior knowledge on dynamic uncertainties is relaxed and a class of more
general chaotic systems is considered as well as robustness to the approximation error is improved. It can be proven that
the closed-loop system is stable in the sense that all the variables are bounded. Simulation example for the unified chaotic
systems is given to verify the effectiveness of the proposed method.
This work was supported in part by the National Natural Science Foundation of China (60874056) and the Foundation of Educational
Department of Liaoning Province (2008312). 相似文献
112.
1.IntroductionInthispaper,weconsideralineartime--invariaflt'system{EI;," "(1)withthematricesE,AER",BER"m,CeRP",alldEissingular.Thebehaviorofasingularsystemdependscriticallyontheeigenstructureofthepencil(E,A).Tilepencil(E,A)andthecorrespondingsystem(1)aresaidtoberegularifdet(orE--dA)/0forsome(a,0)eCZ(2)andtheyaresaidtohaveindexatmostoneifthedimensionofthelargestnilpotelltblock(whichcorrespondstoaninfinitepole)intheKroneckercanonicalformofthepencil(E,A)islessthanorequalto..e[3'12]… 相似文献
113.
针对当前大学课堂学生学习自主性缺乏、能力培养被弱化的现状,在调研的基础上,根据认知心理学的心理机制,提出了能力集成课堂教学模式,改变单入单出的传统教学模式,旨在发挥课堂教学应有的作用,增强学生上课的参与意识,培养、锻炼学生的多方面综合能力. 相似文献
114.
《Physics letters. A》2014,378(32-33):2423-2428
This Letter is devoted to results of the both experimental and theoretical studies of electromagnetic radiation output power gain in the low-voltage microwave generator with a virtual cathode (vircator) under an external harmonic signal leading to the preliminary velocity modulation of the electron beam. The simple theoretical model of the electron beam with virtual cathode in a diode gap with retarding field under the external signal has been developed. The theoretical and numerical analysis have shown the possibility of power amplification in the vircator under the external influence. Obtained results of the theoretical consideration are proven by the experimental study. 相似文献
115.
We put a two-level atom into a cavity comprising a dielectric with output coupling. An analytical expression of the dynamical Casimir–Polder force in such a system is obtained when the system starts from a partially dressed state. And the effects of several relevant parameters of the system on the time-dependent force are also discussed. 相似文献
116.
《Applied Mathematical Modelling》2014,38(5-6):1685-1697
This paper is concerned with the problem of output feedback stabilization for a class of discrete-time systems with sector nonlinearities and imperfect measurements. A unified control law model is proposed to take the network-induced delay, random packet dropout and measurement quantization into consideration simultaneously. By choosing appropriate Lyapunov functional, a new stability condition, which is dependent on multiple network status, is established for the resulting closed-loop system. Based on the result, a design criterion for the static output feedback controller is formulated in the form of nonconvex matrix inequalities, and the cone complementary linearization (CCL) procedure is exploited to solve the nonconvex feasibility problem. Incidentally, a less conservative synthesis method is also developed for the state feedback stabilization purpose. Finally, two illustrative examples are provided to illustrate the effectiveness and applicability of the proposed design method. 相似文献
117.
M. M. Doyley B. Jadamba M. Sama B. Winkler 《Numerical Functional Analysis & Optimization》2014,35(7-9):984-1017
The primary objective of this work is a detailed theoretical and computational study of the elasticity imaging inverse problem for tumor identification within the human body. Apart from this inverse problem's important and interesting application, it also poses noteworthy mathematical challenges since the underlying mathematical model is a system of elasticity involving incompressibility. This gives rise to the “locking” effect and special treatment is necessary for both the direct and inverse problems. To study the inverse problem in an optimization framework, we introduce a general computational scheme for handling parameter identification in saddle point problems along with the introduction and analysis of a new energy output least-squares objective functionals. We also present a treatment of the identification of discontinuous elasticity coefficients using the total variation regularization method. General formulas for the computation of the coefficient-to-solution map and a complete convergence analysis are given for the continuous problem as well as for its discrete analogue. Discrete formulas and implementation issues are discussed in detail and numerical examples for smooth and discontinuous coefficients are given. 相似文献
118.
119.
C.-Y. Wen J.-Z. LinM.-Y. Chen L.-Q. ChenT.-K. Liang 《Journal of magnetism and magnetic materials》2011,323(10):1258-1262
The interfacial instability of miscible magnetic fluids in a Hele-Shaw Cell is studied experimentally, with different magnitudes and sweep rates of the external magnetic field. The initial circular oil-based magnetic fluid drop is surrounded by the miscible fluid, diesel. The external uniform magnetic fields induce small fingerings around the initial circular interface, so call labyrinthine fingering instability, and secondary waves. When the magnetic field is applied at a given sweep rate, the interfacial length grows significantly at the early stage. It then decreases when the magnetic field reaches the preset values, and finally approaches a certain asymptotic value. In addition, a dimensionless parameter, Pe, which includes the factors of diffusion and sweep rate of the external magnetic field, is found to correlate the experimental data. It is shown that the initial growth rate of the interfacial length is linearly proportional to Pe for the current experimental parameter range and is proportional to the square root of the sweep rate at the onset of labyrinthine instability. 相似文献
120.