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Parameters identification of chaotic systems based on artificial bee colony algorithm combined with cuckoo search strategy

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Science China(Technological Sciences) 2018年第3期61卷 417-426页

作者： DING ZhengHao LU ZhongRong liu jike Department of Applied Mechanics Sun Yat-sen University

Artificial bee colony(ABC) algorithm is motivated by the intelligent behavior of honey bees when seeking a high quality food source. It has a relatively simple structure but good global optimization ability. In order to balance its global search and local search abilities further, some improvements for the standard ABC algorithm are made in this study. Firstly, the local search mechanism of cuckoo search optimization(CS) is introduced into the onlooker bee phase to enhance its dedicated search; secondly, the scout bee phase is also modified by the chaotic search mechanism. The improved ABC algorithm is used to identify the parameters of chaotic systems, the identified results from the present algorithm are compared with those from other algorithms. Numerical simulations, including Lorenz system and a hyper chaotic system, illustrate the present algorithm is a powerful tool for parameter estimation with high accuracy and low deviations. It is not sensitive to artificial measurement noise even using limited input data.

关键词： chaotic systems parameter estimation swarm intelligence ABC CS local search

Flutter analysis of an airfoil with nonlinear damping using equivalent linearization

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Chinese Journal of Aeronautics 2014年第1期27卷 59-64页

作者： Chen Feixin liu jike Chen Yanmao Department of Mechanics Sun Yat-sen University

The equivalent linearization method （ELM） is modified to investigate the nonlinear flut- ter system of an airfoil with a cubic damping. After obtaining the linearization quantity of the cubic nonlinearity by the ELM, an equivalent system can be deduced and then investigated by linear flut- ter analysis methods. Different from the routine procedures of the ELM, the frequency rather than the amplitude of limit cycle oscillation （LCO） is chosen as an active increment to produce bifurca- tion charts. Numerical examples show that this modification makes the ELM much more efficient. Meanwhile, the LCOs obtained by the ELM are in good agreement with numerical solutions. The nonlinear damping can delay the occurrence of secondary bifurcation. On the other hand, it has marginal influence on bifurcation characteristics or LCOs.

关键词： Airfoil flutter Bifurcation Cubic damping Equivalent linearization Limit cycle oscillation

ANALYTICAL SOLUTIONS TO STRESS CONCENTRATION PROBLEM IN PLATES CONTAINING RECTANGULAR HOLE UNDER BIAXIAL TENSIONS

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Acta Mechanica Solida Sinica 2008年第5期21卷 411-419页

作者： Yi Yang jike liu Chengwu Cai School of Civil Engineering and Transportation South China University of Technology Guangzhou 510640 China Department of Mechanics Sun Yat-sen University Guangzhou 510275 China

The stress concentration problem in structures with a circular or elliptic hole can be investigated by analytical methods. For the problem with a rectangular hole, only approximate results are derived. This paper deduces the analytical solutions to the stress concentration problem in plates with a rectangular hole under biaxial tensions. By using the U-transformation technique and the finite element method, the analytical displacement solutions of the finite element equations are derived in the series form. Therefore, the stress concentration can then be discussed easily and conveniently. For plate problem the bilinear rectangular element with four nodes is taken as an example to demonstrate the applicability of the proposed method. The stress concentration factors for various ratios of height to width of the hole are obtained.

关键词： U-transformation stress concentration rectangular hole analytical solution biaxial tension

Calculations of the bounds on limit cycle oscillations in nonlinear aeroelastic systems based on equivalent linearization

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Science China(Technological Sciences) 2014年第6期57卷 1249-1256页

作者： CHEN FeiXin liu jike CHEN YanMao Department of Mechanics Sun Yat-sen University

The nonlinear aeroelastic system of an airfoil with an external store was investigated,with emphasis on the bounds of limit cycle oscillations(LCOs).Based on the equivalent linearization,an approach was proposed to calculate the bounds on LCOs over the full flight *** bounds are determined directly without solving LCOs one by one as the flow speed *** presented approach can provide us with the maximal LCO amplitudes and the lower threshold for flow speed beyond which LCOs may *** examples show that the obtained bounds are in nice agreement with numerical simulation *** speed threshold can be predicted to a relative error less than 0.1%,and the maximal LCO amplitude to about 3%.The influences of the system parameters on the speed threshold for speed were investigated efficiently by the proposed approach.

关键词： nonlinear aeroelastic limit cycle oscillation bound equivalent linearization

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考虑不确定因素的结构损伤定位方法

固体力学学报 2007年第2期28卷 189-194页

作者：汤凯刘济科中山大学应用力学与工程系广州510275

将应变模态作为实测资料应用概率方法进行结构损伤定位.采用的模态误差考虑了建模误差和测量误差等不确定因素,避免了测量自由度与模型自由度不匹配的问题.研究了损伤状态搜索策略,并对应变模态和位移模态分别作为实测资料的定位结果进... 详细信息

将应变模态作为实测资料应用概率方法进行结构损伤定位.采用的模态误差考虑了建模误差和测量误差等不确定因素,避免了测量自由度与模型自由度不匹配的问题.研究了损伤状态搜索策略,并对应变模态和位移模态分别作为实测资料的定位结果进行了比较,表明采用应变模态具有更高的定位精度.

关键词：应变模态概率方法相对最大后验概率启发式搜索

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基于人工神经网络的复杂结构模态匹配

振动与冲击 2006年第1期25卷 42-46页

作者：汤凯刘济科中山大学应用力学与工程系广州510275

对结构模态匹配方法进行简单评述,并提出了一种基于人工神经网络的复杂结构模态匹配方法。该方法能够准确匹配复杂结构模态向量,同时可以有效消除由于试验模态测量中测点不足、测点布置不当、测量不准确等因素导致的试验模态向量间的空... 详细信息

对结构模态匹配方法进行简单评述,并提出了一种基于人工神经网络的复杂结构模态匹配方法。该方法能够准确匹配复杂结构模态向量,同时可以有效消除由于试验模态测量中测点不足、测点布置不当、测量不准确等因素导致的试验模态向量间的空间混叠影响。考虑实际工程中能够获得的训练样本数目有限,采用了轮换式学习方法有效扩展了学习样本集。算例表明,本方法合理可靠,在实际工程中有广泛的应用前景。

关键词：模态匹配人工神经网络空间混叠轮换式学习方法

基于支持向量回归的迭代序列响应面可靠度计算方法

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机械强度 2008年第6期30卷 916-920页

作者：赵卫刘济科暨南大学力学与土木工程系广州510632 中山大学应用力学与工程系广州510275

在基于支持向量回归的响应面可靠度计算方法基础上,采用试验设计中设计试验点的方法生成样本点,构造训练集,并对可靠度计算的迭代序列响应面方法进行改进。计算结果表明,与采用拉丁超立方抽样和常规梯度优化法求解的基于支持向量回归响... 详细信息

在基于支持向量回归的响应面可靠度计算方法基础上,采用试验设计中设计试验点的方法生成样本点,构造训练集,并对可靠度计算的迭代序列响应面方法进行改进。计算结果表明,与采用拉丁超立方抽样和常规梯度优化法求解的基于支持向量回归响应面方法相比,文中方法所需样本更少、收敛更快、结果更理想。

关键词：支持向量回归迭代序列响应面可靠度计算

基于时域响应灵敏度分析的非线性系统参数识别

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振动与冲击 2018年第21期37卷 213-219页

作者：刘广刘济科吕中荣中山大学航空航天学院力学系广州510275

基于响应灵敏度分析的有限元模型修正法已广泛应用于线性结构系统的局部损伤和裂纹参数等的识别。尝试将该方法推广应用到非线性系统的参数识别中。从非线性系统运动方程出发,通过数值积分得到系统的强迫振动响应,对系统的物理参数求导... 详细信息

基于响应灵敏度分析的有限元模型修正法已广泛应用于线性结构系统的局部损伤和裂纹参数等的识别。尝试将该方法推广应用到非线性系统的参数识别中。从非线性系统运动方程出发,通过数值积分得到系统的强迫振动响应,对系统的物理参数求导得到时域响应对参数的灵敏度,从而构造相应的响应灵敏度矩阵用于参数识别反问题。以Holmes-Duffing非线性系统和物理工程中有着广泛应用的双重sine Gordon非线性系统的参数识别为例,说明方法的应用过程。算例研究了不同的初始参数和测量噪声对识别结果的影响,结果表明响应灵敏度法能准确快速识别非线性系统的参数,并且具有对测量噪声不敏感的优点。

关键词：参数识别非线性系统应灵敏度分析 Holmes-Duffing系统双重sine Gordon系统

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结构损伤诊断的改进灵敏度方法

固体力学学报 2012年第1期33卷 112-118页

作者：杨秋伟刘济科绍兴文理学院土木工程系绍兴312000 中山大学应用力学与工程系广州510275

提出一种改进的灵敏度方法用于工程结构损伤检测中.通过在迭代算法中引入一个"加速"公式来迅速获得足够精确的识别结果,避免了多次迭代,可以大大减少计算花费.用文献[8]和文献[10]中的两个数值算例对所提方法进行了验证,并把结果和原文... 详细信息

提出一种改进的灵敏度方法用于工程结构损伤检测中.通过在迭代算法中引入一个"加速"公式来迅速获得足够精确的识别结果,避免了多次迭代,可以大大减少计算花费.用文献[8]和文献[10]中的两个数值算例对所提方法进行了验证,并把结果和原文中的计算结果进行比较.结果表明:采用改进的方法一般只需经过一次计算即可获得精度更高的识别结果,避免了多次迭代,显著减少了计算花费,显示了改进方法突出的优越性.

关键词：损伤诊断灵敏度频率振型