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1.
Ahmadreza Momeni Amir G. Aghdam 《International Journal of Adaptive Control and Signal Processing》2007,21(10):885-910
Most of the existing switching control techniques are developed specifically for finite-dimensional linear time-invariant (LTI) systems. In many practical applications, however, it is essential to take time delay into consideration in the modelling as the control system can be highly sensitive to delay. In this paper, a multi-model switching control algorithm is proposed for retarded time-delay systems. It is assumed that the plant is represented by a family of known multi-input multi-output, observable, LTI models with multiple delays in the states, and that corresponding to each model in the known family, there exists a high-performance finite-dimensional LTI controller. In addition, it is supposed that a bound on the magnitude of the external inputs and disturbances is available. It is then shown that the proposed switching controller can stabilize the uncertain system, and that under some mild conditions, output tracking can be achieved in the given problem setting. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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Abstract. In this paper the problems of parameter estimation and order determination of an exponential (EX) model are studied in the time domain. In order to estimate the parameters, the parameter equations of an EX model are given in terms of the autocorrelation function, which is similar to the Yule-Walker equations of an autoregressive moving-average model. Estimates of parameters are obtained with the aid of the parameter equations and theorems are proved relating the convergence rate and asymptotic distribution of the estimates. We present two kinds of methods for estimating the order and prove that the estimates of the order are consistent. 相似文献
4.
Cui‐Zhen Yao 《Asian journal of control》2013,15(5):1531-1537
This article considers stabilization of a one‐dimensional Schrödinger equation with variable coefficient and boundary observation which suffers from an arbitrary given time delay. We design an observer and predictor to stabilize the system. The state is estimated in the time span where the observation is available, and also predicted in the time interval where the observation is not available. It is shown that the estimated state feedback stabilizes the system exponentially. A numerical simulation is presented to illustrate the effect of the stabilizing controller. 相似文献
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本文通过表述传播学五大要素在《交换空间》栏目中的体现,主要介绍了家装从规划设计到具体实施的整个过程在《交换空间》栏目中的体现,分析了《交换空间》作为一种具体的可实施性强的节目对家庭装饰装修理念新的诠释。 相似文献
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采用遗传算法建立贝叶斯网络的优化学习结构,一直是贝叶斯网络研究倍受关注的课题.传统遗传算法的个体设计存在需要反复进行无环性检验的问题,降低了进化效率.针对这个问题,提出一种新的个体编码方式.考虑到进化过程中家族得分的可继承性,提出基于家族继承的结构评分改进算法,进而设计相应的改进遗传算法.实验结果表明,改进算法在BN建网精度与效率上都得到明显提升. 相似文献
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Demographic data show that major changes have been occurring in the everyday lives of families over the last generation, with the majority of mothers of young children in the workforce and an increasing number of men and women assuming caregiving responsibilities for older relatives. Thus, the 2 primary identities of most adults, defined by their multiple family and work roles, need to be coordinated in ways that promote positive family outcomes, returns on investments for employers, and societal values. Despite changes in the workforce, the world of work is still largely organized for a family model that is increasingly rare--one with a stay-at-home caregiver. Recommendations based on psychological and other social science research are offered to align the needs of working families and employers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Ju Li 《Journal of Computer-Aided Materials Design》2005,12(2-3):141-159
We discuss several post-processing issues in molecular dynamics (MD) calculation of lattice thermal conductivity using the
Green–Kubo formula. For crystals with high thermal conductivity such as SiC, converting the MD raw data on heat current fluctuations
into thermal conductivity result is non-trivial. One can accelerate the process using Fast Fourier Transform and the spectral
method. A few mathematical subtleties are cleared up. Due to finite data length, integration of the correlation function must
be terminated before noise takes over; two termination criteria are proposed which give reasonable results for crystalline
β-SiC. A simple solvable model that illustrates the above points and can be used for code-checking is presented. 相似文献
10.
蔡四青 《昆明理工大学学报(自然科学版)》1997,22(5):43-46
进入90年代以来,经济的发展又一次推动着经济理论的发展和演变.新经济的现象不断出现,使得经济学靠模型和计算机未能找到解决问题的答案,正统经济学再次受到严峻的挑战.与此同时,行为经济学,以人类的行为作为基本研究对象的经济理论,正逐步发展起来.本文将介绍行为经济学的产生和发展、主要理论观点以及一些行为分析对中国社会经济发展的启示. 相似文献