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71.
Wen-Jer Chang Liang-Zhi Liu Cheung-Chieh Ku 《International Journal of Control, Automation and Systems》2011,9(3):550-557
This paper investigates the fuzzy control problem of a class of nonlinear continuous-time stochastic systems with achieving
the passivity performance. A model-based observer feedback fuzzy control utilizing the concept of so-called parallel distributed
compensation (PDC) is employed to stabilize the class of nonlinear stochastic systems that are represented by the Takagi-Sugeno
(T-S) fuzzy models. Based on the Lyapunov criteria, the Linear Matrix Inequality (LMI) technique is used to synthesize the
observer feedback fuzzy controller design such that the closed-loop system satisfies stability and passivity constraints,
simultaneously. Finally, a numerical example is given to demonstrate the applicability and effectiveness of the proposed design
method. 相似文献
72.
In this paper we study a class of CQ Horn functions introduced in Boros et al. (Ann Math Artif Intell 57(3–4):249–291, 2010). We prove that given a CQ Horn function f, the maximal number of pairwise disjoint essential sets of implicates of f equals the minimum number of clauses in a CNF representing f. In other words, we prove that the maximum number of pairwise disjoint essential sets of implicates of f constitutes a tight lower bound on the size (the number of clauses) of any CNF representation of f. 相似文献
73.
Katarzyna TyszczukAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(2):899-905
The properties of the lead film electrode designed for adsorptive stripping voltammetric measurements of organic compounds were examined by electrochemical and microscopic techniques. The effect of Pb(II) concentration, the influence of deposition potential and time of the lead film formation on the determination of bleomycin at an in situ lead-coated glassy carbon electrode have been studied. Atomic force microscopy (AFM) was used to characterize the Pb crystallite growth on the glassy carbon surface. The morphology of the deposits was evaluated and its influence on the bleomycin responses was discussed. 相似文献
74.
Recently, Wang et al. showed that two new verifier-free remote user password authentication schemes, Ku-Chen's scheme and Yoon et al.'s scheme, are vulnerable to an off-line password guessing attack, a forgery attack, and a denial-of-service attack, and then proposed an improved scheme for the real application in resource-limited environments. Unfortunately, we find that Wang et al.'s scheme is still vulnerable to an impersonation attack and an off-line password guessing attack. In addition, Wang et al.'s scheme is not easily reparable and is unable to provide perfect forward secrecy. Finally, we propose an improved scheme with better security strength. 相似文献
75.
Fan Zhang Robert Hager Seung-Hoe Ku Choong-Seock Chang Stephen C. Jardin Nathaniel M. Ferraro E. Seegyoung Seol Eisung Yoon Mark S. Shephard 《Engineering with Computers》2016,32(2):285-293
XGC1 and M3D-C 1 are two fusion plasma simulation codes being developed at Princeton Plasma Physics Laboratory. XGC1 uses the particle-in-cell method to simulate gyrokinetic neoclassical physics and turbulence (Chang et al. Phys Plasmas 16(5):056108, 2009; Ku et al. Nucl Fusion 49:115021, 2009; Admas et al. J Phys 180(1):012036, 2009). M3D-\(C^1\) solves the two-fluid resistive magnetohydrodynamic equations with the \(C^1\) finite elements (Jardin J comput phys 200(1):133–152, 2004; Jardin et al. J comput Phys 226(2):2146–2174, 2007; Ferraro and Jardin J comput Phys 228(20):7742–7770, 2009; Jardin J comput Phys 231(3):832–838, 2012; Jardin et al. Comput Sci Discov 5(1):014002, 2012; Ferraro et al. Sci Discov Adv Comput, 2012; Ferraro et al. International sherwood fusion theory conference, 2014). This paper presents the software tools and libraries that were combined to form the geometry and automatic meshing procedures for these codes. Specific consideration has been given to satisfy the mesh configuration and element shape quality constraints of XGC1 and M3D-\(C^1\). 相似文献
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针对传统的模糊核聚类算法(FKCM)需给出聚类个数,且对初始值敏感、易陷入局部最优的缺点,本文提出了一种基于高斯核化有效性指标的自适应优选聚类数的模糊核聚类算法(GKVI-AOCN-FKCM)。利用基于密度和距离的方法选取初始聚类中心,克服了对初始值的敏感,提高了聚类效率。然后用高斯核函数核化后的有效性指标评价聚类效果并自动确定最佳分类数,从而无监督地实现对数据集的模糊划分。对Iris数据集的仿真实验及石脑油属性数据分类的应用验证了算法的可行性和有效性。 相似文献
78.
强耦合多变量模糊温度控制系统的研究 总被引:1,自引:0,他引:1
针对强耦合多变量温度控制系统进行了研究,系统是以中央温度和均匀温度作为输入,以加热元件和热风速度作为输出,形成了双输入-双输出温度控制系统。采用具有解耦功能的模糊控制,介绍了控制算法的步骤,根据实际情况提出了分段控制算法。实践表明该系统切实可行,达到了所要求的控制精度和目的。 相似文献
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