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范荣 《电脑编程技巧与维护》2011,(2):11-13,22
重点在于融和丰富字特征作为消歧知识以提高分类性能和引入不等式平滑技术来克服数据稀疏问题,同时不等式平滑技术还使特征选择嵌入到参数估计过程中,显著压缩模型规模。 相似文献
43.
Applying dither to highly nonlinear systems may suppress chaotic phenomena, but dynamic performance, such as convergence rate and disturbance attenuation, is usually not guaranteed. This paper presents a dithered H∞ robust fuzzy control scheme to stabilize chaotic systems that ensures disturbance attenuation bounds. In the proposed scheme, Takagi-Sugeno (T-S) fuzzy linear models are used to describe the relaxed models of the dithered chaotic system, and fuzzy controllers are designed based on an extension to the concept of parallel distributed compensation (PDC). Sufficient condition for the existence of the H∞ robust fuzzy controllers is presented in terms of a novel linear matrix inequalities (LMI) form which takes full consideration of modeling error and disturbances, but cannot be solved by the standard procedures. In order to solve the LMI problem and to identify the chaotic systems as T-S fuzzy modes, we propose a compound optimization strategy called the island-based random-walk algorithm (IRA). The algorithm is composed of a set of communicating random-walk optimization procedures concatenated with the down-hill simplex method. The design procedure and validity of the proposed scheme is demonstrated via numerical simulation of the dithered fuzzy control of a chaotic system. 相似文献
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研究一类T-S模糊广义系统的容许性条件和H∞控制问题. 首先将原系统表示成增广系统, 进而基于新的模糊Lyapunov函数和模糊控制器得到容许性条件. 所得开环容许条件不要求子系统是容许的; 闭环容许条件中不含有控制输入矩阵与控制增益矩阵的乘积项. 对于H∞控制问题, 利用隶属度函数的性质对H∞控制条件进行了放宽, 并得到了改进的严格线性矩阵不等式(LMI)形式的H∞控制条件. 数值算例表明所得结论较已有文献具有较小的保守性. 相似文献
46.
The aim of this paper is to study the invariant and attracting sets of impulsive delay difference equations with continuous variables. Some criteria for the invariant and attracting sets are obtained by using the decomposition approach and delay difference inequalities with impulsive initial conditions. 相似文献
47.
Design of variable structure control for fuzzy nonlinear systems 总被引:1,自引:0,他引:1
In this paper, the variable structure control problem is presented for Takagi–Sugeno fuzzy systems with uncertainties and external disturbances. The sliding surfaces for the T–S fuzzy system are proposed by using a Lyapunov function and a fuzzy Lyapunov function, respectively. And we design the variable structure controllers such that the global T–S fuzzy system confined on the sliding surfaces is asymptotically stable. Two examples are given to illustrate the effectiveness of our proposed methods. 相似文献
48.
New delay-dependent criterion for the stability of recurrent neural networks with time-varying delay
This paper is concerned with the global asymptotic stability of a class of recurrent neural networks with interval time-varying
delay. By constructing a suitable Lyapunov functional, a new criterion is established to ensure the global asymptotic stability
of the concerned neural networks, which can be expressed in the form of linear matrix inequality and independent of the size
of derivative of time varying delay. Two numerical examples show the effectiveness of the obtained results.
Supported by the National Natural Science Foundation of China (Grant Nos. 60534010, 60728307, 60774048, 60774093), the Program
for Cheung Kong Scholars and Innovative Research Groups of China (Grant No. 60521003) and the National High-Tech Research
& Development Program of China (Grant No. 2006AA04Z183), China Postdoctoral Sciencer Foundation (Grant No. 20080431150), and
the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 200801451096) 相似文献
49.
线性时滞系统稳定性分析综述 总被引:3,自引:0,他引:3
时滞在工程领域广泛存在,对此综述了线性时滞系统的稳定性研究方法.从频域和时域两个角度详细介绍了各种方法的特点,着重讨论基于线性矩阵不等式(LMI)的分析方法,指出保守性是分析的重点.对现有结果的保守性进行比较和评述,并提出了改进的思路. 相似文献
50.