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71.
A controller is designed to realize the synchronization between
chaotic systems with different orders. The structure of the
controller, the error equations and the Lyapunov functions are
determined based on stability theory. Hyperchaotic Chen system and
Rossler system are taken for example to demonstrate the method to be
effective and feasible. Simulation results show that all the state
variables of Rossler system can be synchronized with those of
hyperchaotic Chen system by using only one controller, and the error
signals approach zero smoothly and quickly. 相似文献
72.
We say a family
of strings is an UMFF if every string has a unique maximal factorization over
. Then
is an UMFF iff
and y non-empty imply
. Let L-order denote lexicographic order. Danh and Daykin discovered V-order, B-order and T-order. Let R be L, V, B or T. Then we call r an R-word if it is strictly first in R-order among the cyclic permutations of r. The set of R-words form an UMFF. We show a large class of B-like UMFF. The well-known Lyndon factorization of Chen, Fox and Lyndon is the L case, and it motivated our work. 相似文献
73.
74.
Han‐Chung Wu Ioseba I. Soraluze Li‐Po Chen Ping‐Chih Huang Chun‐Hsiung Kuei 《中国化学会会志》2013,60(9):1127-1134
This study employed the non‐destructive techniques to analyze and examine the artworks of the Taiwanese artist Cheng‐Po Chen (1895‐1947) for disclosing the damage to Chen's artworks and determine his creation habits. Ten pieces of artworks that required restoration were examined using ultraviolet examination techniques. Based on the differences in their fluorescence characteristics, various parts of these works were shown to have been retouched, thus, original and retouched regions were distinguished. Examining these works using Infrared instrument revealed that Chen did not use charcoal to prepare drafts, and he directly applied oil paint to the canvases. Subsequently, these two examination techniques were adopted to examine sketches. The results showed that residues imprinted on them cause of storage methods were organic materials from charcoal and not carbon granules. The X‐ray examination identified numerous creations beneath the surface of several artworks. The X‐ray fluorescence spectrometer was used for elemental analysis of the pigments. The results corresponded with the pigments listed in Chen's purchase form, thus, we summarized the composition of palettes used by Chen. In general, this study acquired a considerable amount of information from the pigment examinations and established a database of the pigments that Chen commonly employed in his artworks. 相似文献
75.
Adaptive fuzzy control‐based projective synchronization of uncertain nonaffine chaotic systems 下载免费PDF全文
This article aims to introduce a projective synchronization approach based on adaptive fuzzy control for a class of perturbed uncertain multivariable nonaffine chaotic systems. The fuzzy‐logic systems are employed to approximate online the uncertain functions. A Lyapunov approach is used to design the parameter adaptation laws and to demonstrate the boundedness of all signals of the closed‐loop system as well as the convergence of the synchronization errors to bounded residual sets. Finally, numerical simulation results are presented to verify the feasibility and effectiveness of the proposed synchronization system based on fuzzy adaptive controller. © 2014 Wiley Periodicals, Inc. Complexity 21: 180–192, 2015 相似文献
76.
77.
用两种不同的方法——主动控制同步法和自适应控制同步法实现超混沌Chen系统和超混沌Roessler系统的异结构同步,各自设计了不同的控制器,使得响应系统与驱动系统同步.当参数已知时,采用主动控制法,方法简单有效且不需要构造Lyapunov函数,实现同步的时间短;当系统参数未知或结构不确定时,基于Lyapunov稳定性理论,给出自适应同步控制器的系统设计过程和参数自适应律,使得系统达到同步同时识别未知参数,数值模拟验证了两种方法的有效性。 相似文献
78.
In this paper, a nonlinear control scheme of two identical hyperchaotic Chert systems is developed to realize their modified projective synchronization. We achieve modified projective synchronization between the two identical hyperchaotic systems by directing the scaling factor onto the desired value. With symbolic computation system Maple and Lyapunov stability theory, numerical simulations are given to perform the process of the synchronization. 相似文献
79.
将子流形的位置向量分解成水平分量和垂直分量,运用活动标架法研究伪欧氏空间的伪球面子流形。得到紧致类空子流形是伪球面子流形的两个充要条件:1)子流形的支撑函数是常值函数;2)子流形位置向量的水平分量是调和的。同时,给出具有平行平均曲率向量场的子流形是伪球面子流形的一个充要条件。特别地,对于Chen子流形,若它具有非迷向的平行平均曲率向量场且其支撑函数有固定符号,则它是伪球面子流形。 相似文献
80.
It is shown that the N-lines in the luminescence spectra of the two spinels ZnAl2O4:Cr3+ and MgAl2O4:Cr3+ exhibit quite similar dependencies on chromium concentration, excitation frequency, and thermal treatment of the samples. While most of these lines are structure dependent, the line N4 at and two very weak lines are in both cases due to chromium-pairs. The exchange Hamiltonian Hex = JS1 · S2 + j(S1 · S2)2 used for the ground-state splitting is fitted by the parameters J = 40.9 cm?1, j = 1.5 cm?1 and J = 45.6 cm?1, j = 2.0 cm?1 for ZnAl-spinel and MgAl-spinel, respectively. The differences between the spectra of low-doped and high-doped samples are in both cases caused by the existence of a phonon sideband of the N4-line, which is in many respects similar to the well-known phonon side band of the R-line. 相似文献