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参考模糊集合构造方法及模糊模型辨识 总被引:3,自引:0,他引:3
本文提出了一种基于参考模糊集的模糊模型辨识方法,探讨了模型结构和模糊关系的辨识问题.在隶属函数的定义上引入了优化算法,最终将辨识问题转化为优化问题.文中给出了具体的辨识算法,仿真实例表明该模型辨识方法具有满意的精度. 相似文献
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复杂系统的递阶模糊辨识 总被引:2,自引:0,他引:2
针对Takagi_Sugeno模糊模型 (T_S模型 )严重的维数灾问题, 借鉴GMDH算法, 提出了一种新的复杂系统递阶模糊辨识方法. 本文首先详细描述了由两输入变量的特殊T_S模型所组成的递阶模糊模型 ;然后提出了具体的辨识该递阶模糊模型的方法. 该方法的特点是 :a)在结构辨识阶段, 用FCM模糊聚类方法评价系统中每个输入变量的重要性, 以便构造合理的递阶模糊模型 ;b)预先合理地确定了所要辨识的参数的初始值, 用扩展卡尔曼滤波方法可很快地得到这些参数. 最后, 给出的仿真实例说明了本文辨识方法的有 相似文献
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教师教学评估是高等院校教学质量管理的重要环节,对提高课堂教学质量具有积极意义和重要作用.教师教学评估是一个多目标、多层次的模糊综合评判问题,在模糊综合评判中将有关的模糊概念用模糊集合表示,通过模糊运算获得用模糊集合表示的评价结果.针对教学评估体系输入和输出之间的复杂关系,在介绍了模糊变换的基础上,提出了适用于教师教学评估的多目标多级模糊综合评判模型,且用实例进行了说明. 相似文献
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结合犹豫模糊集和区间梯形模糊数,提出了区间犹豫梯形模糊集的概念;针对信息集成过程中需要考虑输入变量之间的相互影响,提出了区间犹豫梯形模糊Bonferroni Mean(IVHTrFBM)算子和区间犹豫梯形模糊几何Bonferroni Mean(IVHTrFGBM)算子,并讨论了它们的性质和特例;根据输入变量的重要程度不同,提出了区间犹豫梯形模糊加权Bonferroni Mean(IVHTrFWBM)算子和区间犹豫梯形模糊加权几何Bonferroni Mean(IVHTrFWGBM)算子。最后,提出了基于IVHTrFWBM算子和IVHTrFWGBM算子的区间犹豫梯形模糊多属性决策方法,并通过实例进行验证。 相似文献
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教师教学评估是高等院校教学质量管理的重要环节,对提高课堂教学质量具有积极意义和重要作用。教师教学评估是一个多目标、多层次的模糊综合评判问题,在模糊综合评判中将有关的模糊概念用模糊集合表示,通过模糊运算获得用模糊集合表示的评价结果。针对教学评估体系输入和输出之间的复杂关系,在介绍了模糊变换的基础上,提出了适用于教师教学评估的多目标多级模糊综合评判模型,且用实例进行了说明。 相似文献
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基于模糊集合的模糊建模捕述复杂、病态、非线性系统的特性是一种有效方法.文中讨论了从样本数据中通过正交变换和模糊聚类获取模糊规则的方法.利用正交最小二乘对模糊聚类的结果进行变换,采用CGS(Classical Gram—Schmidt)方法确定对建模贡献大的规则,删除对建模贡献小的规则,并对模型中的参数进行估计,能够同时模对糊模型的结构和参数进行辨识.仿真结果表明,提出的方法能够对非线性系统进行模糊建模. 相似文献
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An algorithm for bounded-error identification of nonlinear systems based on DC functions 总被引:1,自引:0,他引:1
This paper presents a guaranteed method for the parameter estimation of nonlinear models in a bounded-error context. This method is based on functions which consists of the difference of two convex functions, called DC functions. The method considers DC representations of the functional form of the dynamic system to obtain an outer bound of the set of parameters that are consistent with the measurements, the system and the considered bounded error. At each iteration, the proposed algorithm solves several convex optimization problems to discard from the initial search region subregions that are proved not consistent. This operation is repeated while the obtained solution is improved. Four examples are provided to clarify the proposed identification algorithm. 相似文献
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A virtual closed loop method for closed loop identification 总被引:2,自引:0,他引:2
Indirect methods for the identification of linear plant models on the basis of closed loop data are based on the use of (reconstructed) input signals that are uncorrelated with the noise. This generally requires exact (linear) controller knowledge. On the other hand, direct identification requires exact plant and noise modelling (system in the model set) in order to achieve accurate results, although the controller can be non-linear. In this paper, a generalized approach to closed loop identification is presented that includes both methods as special cases and which allows novel combined methods to be generated. Besides providing robustness with respect to inexact controller knowledge, the method does not rely on linearity of the controller nor on exact noise modelling. The generalization is obtained by balancing input-noise decorrelation against noise whitening in a user-chosen flexible fashion. To this end, a user-chosen virtual controller is used to parametrize the plant model, thereby generalizing the dual-Youla method to cases where knowledge of the controller is inexact. Asymptotic bias and variance results are presented for the method. Also, the benefits of the approach are demonstrated via simulation studies. 相似文献
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变风量空调末端(VAVBOX)是变风量系统的关键部位,其运行的状况将直接影响空调系统的整个运行效果。本文主要论述了对压力有关型变风量末端控制回路进行了系统辨识,风阀模型采用开环辨识的方法,房间模型辨识中采用了闭环辨识。为研究变风量空调末端(VAVBOX)在室内温度方面的精确控制与抗扰问题打下了坚实基础。 相似文献
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An algorithm for the exact least-squares identification of an approximate continuous-time time-delay system is derived and its operation verified by simulation. 相似文献
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An on-line parameter identification problem is posed and solved for discrete-time systems with general knowledge on the level of the inherent information noise. The knowledge can be the bound on either the magnitude or the finite-index
p norm, pε[1, ∞), of the noise. Based on the knowledge, a switching type gradient algorithm (or called gradient algorithm with dead zone) is proposed to estimate the parameters of the system from the available input-output data. In spite of the existence of the noise, this on-line algorithm guarantees that the estimation error is monotonically decreasing, and the parameter estimate is convergent to a steady-state value under a mild condition. Furthermore, the algorithm is stable in the sense that the estimation error will converge to zero as the bound on the noise gradually diminishes. 相似文献
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Håkan Hjalmarsson Jonas Mårtensson Cristian R. Rojas Torsten SöderströmAuthor vitae 《Automatica》2011,47(12):2704-2712
Errors-in-variables estimation problems for single-input–single-output systems with Gaussian signals are considered in this contribution. It is shown that the Fisher information matrix is monotonically increasing as a function of the input noise variance when the noise spectrum at the input is known and the corresponding noise variance is estimated. Furthermore, it is shown that Whittle’s formula for the Fisher information matrix can be represented as a Gramian and this is used to provide a geometric representation of the asymptotic covariance matrix for asymptotically efficient estimators. Finally, the asymptotic covariance of the parameter estimates for the system dynamics is compared for the two cases: (i) when the model includes white measurement noise on the input and the variance of the noise is estimated, and (ii) when the model includes only measurement noise on the output. In both cases, asymptotically efficient estimators are assumed. An explicit expression for the difference is derived when the underlying system is subject only to measurement noise on the output. 相似文献
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曾建一 《自动化技术与应用》2007,26(8):74-76
由于人体指纹具有唯一性和不变性,使得指纹识别与传统身份识别的方法相比具有更高的安全性和易用性.本文阐述了生物特征识别的发展历史、应用背景,并着重介绍指纹识别系统的工作流程、分类及研究现状. 相似文献