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211.
Choon Ki Ahn 《Nonlinear dynamics》2010,60(4):703-711
In this paper, we propose a new ℋ∞ synchronization strategy, called a fuzzy delayed output feedback ℋ∞ synchronization (FDOFHS) strategy, for chaotic systems in the presence of external disturbance. Based on Lyapunov–Krasovskii
theory, the T–S fuzzy model, and a delayed feedback control scheme, the FDOFHS controller can guarantee stable synchronization.
Furthermore, this controller reduces the effect of external disturbance to an ℋ∞ norm constraint. The proposed controller can be obtained by solving the linear matrix inequality (LMI) problem. A simulation
study is presented to demonstrate the validity of the proposed FDOFHS approach. 相似文献
212.
Choon Ki Ahn 《Nonlinear dynamics》2010,60(3):295-302
This paper proposes a new neural network ?∞ synchronization (NNHS) scheme for unknown chaotic systems. In the proposed framework, a dynamic neural network is constructed as an alternative to approximate the chaotic system. Based on this neural network and linear matrix inequality (LMI) formulation, the NNHS controller and the learning law are presented to reduce the effect of disturbance to an ?∞ norm constraint. It is shown that finding the NNHS controller and the learning law can be transformed into the LMI problem and solved using the convex optimization method. A numerical example is presented to demonstrate the validity of the proposed NNHS scheme. 相似文献
213.
Choon Ki Ahn 《Nonlinear dynamics》2010,61(3):483-489
This paper proposes a new delay-dependent state estimator for Takagi–Sugeno (T-S) fuzzy delayed Hopfield neural networks. By employing a suitable Lyapunov–Krasovskii functional, a delay-dependent criterion is established to estimate the neuron states through available output measurements such that the dynamics of the estimation error is asymptotically stable. It is shown that the design of the proposed state estimator for such neural networks can be achieved by solving a linear matrix inequality (LMI), which can be easily facilitated by using some standard numerical packages. An illustrative example is given to demonstrate the effectiveness of the proposed state estimator. 相似文献
214.
Hyperfine Interactions - Ultrafine Ti-doped CoFe2O4 powders, Ti0.2Co1.2Fe1.6O4, are fabricated by the sol gel method and their magnetic and crystallographic properties depending on annealing... 相似文献
215.
216.
For a Boolean matrix A, a g-inverse of A is a Boolean matrix G satisfying AGA=A, and a Vagner inverse is a g-inverse which in addition satisfies GAG=G. We give algorithms for finding all g-inverses, all Vagner inverses, and all of several other types of inverses including Moore-Penrose inverses. We give a criterion for a Boolean matrix to be regular, and criteria for the various types of inverse to exist. We count the numbers of Boolean matrices having Moore-Penrose and related types of inverses. 相似文献
217.
We characterize homogeneous real hypersurfaces M's of type (A
1), (A
2) and (B) of a complex projective space in the class of real hypersurfaces by studying the holomorphic distribution T
0
M of M. 相似文献
218.
Moustafa A. Gouda 《合成通讯》2017,47(17):1527-1558
The biological and medicinal properties of oxicams and its analogues have prompted enormous research aimed at developing synthetic routes to these heterocycles. This review focuses on the chemical properties associated with this system. 相似文献
219.
Eui‐Jun Choi Chang‐Hyeon Kim Jung‐Ki Park 《Journal of Polymer Science.Polymer Physics》1999,37(17):2430-2438
The polycaprolactone (PCL)/starch blends were prepared by using the starch‐g‐PCL (SGCL) graft copolymers as compatibilizers, and their mechanical properties were correlated with the compatibilizing effect of the SGCL copolymers having various molecular structures. The modulus and strength of the PCL/starch blend were decreased, whereas the percent elongation and the toughness were increased remarkably with the addition of SGCL having appropriate graft structure. These property changes were analyzed in terms of the PCL crystallinity and the interfacial adhesion between the PCL matrix and starch dispersion phases, which were dominated by the compatibilizing effects of the SGCL copolymers. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 2430–2438, 1999 相似文献
220.