Leader‐following consensus problem of heterogeneous multi‐agent systems with nonlinear dynamics using fuzzy disturbance observer

This article considers the leader‐following consensus problem of heterogeneous multi‐agent systems. The proposed multi‐agent system is consisted of heterogeneous agents where each agents have their own nonlinear dynamic behavior. To overcome difficulty from heterogeneous nonlinear intrinsic dynamics of agents, a fuzzy disturbance observer is adopted. In addition, based on the Lyapunov stability theory, an adaptive control method is used to compensate the observation error caused by the difference between the unknown factor and estimated values. Two numerical examples are given to illustrate the effectiveness of the proposed method. © 2013 Wiley Periodicals, Inc. Complexity 19: 20–31, 2014     

Chaotic fractional‐order model for muscular blood vessel and its control via fractional control scheme

This article studies the chaotic and complex behavior in a fractional‐order biomathematical model of a muscular blood vessel (MBV). It is shown that the fractional‐order MBV (FOMBV) model exhibits very complex and rich dynamics such as chaos. We show that the corresponding maximal Lyapunov exponent of the FOMBV system is positive which implies the existence of chaos. Strange attractors of the FOMBV model are depicted to validate the chaotic behavior of the system. We change the fractional order of the model and investigate the dynamics of the system. To suppress the chaotic behavior of the model, we propose a single input fractional finite‐time controller and prove its stability using the fractional Lyapunov theory. In addition, the effects of the model uncertainties and external disturbances are taken into account and a robust fractional finite‐time controller is constructed. The upper bound of the chaos suppression time is also given. Some computer simulations are presented to illustrate the findings of this article. © 2014 Wiley Periodicals, Inc. Complexity 20: 37–46, 2014     

嫦娥三号软着陆轨道设计与控制策略的优化模型

针对嫦娥三号软着陆轨道设计与控制策略问题,在合理假设的前提下,建立动力学模型,求解得到了嫦娥三号着陆准备轨道近月点和远月点的速度。针对软着陆过程的6个阶段,通过受力分析,建立了嫦娥三号运动的微分方程模型,以燃料消耗最小为优化目标,以每个阶段的起止状态为约束条件,将软着陆轨道的优化设计问题转化为主发动机推力的泛函极值问题,并将其控制函数转化为近似的多项式函数优化问题。运用四阶Runge-Kutta差分迭代方法进行求解计算,从而得到各个阶段的最优控制函数和控制策略。结果表明,嫦娥三号软着陆过程耗时695s,消耗燃料1 269.1kg。     

基于非适应性组合群测的多路存取信道模型的构作

在多路存取信道中当前用户的信息传输是计算机通信网络的一个重要内容,基于组合群测理论构作了多路存取信道模型,介绍了它在多路存取信道中当前用户信息传输方面的应用.     

考虑投资者心理预期的投资性商品价格运行稳定性识别与反馈控制机制设计

以投资性商品的价格运行系统为研究对象,引入反映投资者心理预期的变量,对传统的蛛网模型加以改进,并据此构建非均衡市场环境下投资性商品价格运行开环系统模型,对非均衡市场环境下投资性商品市场价格运行的稳定性进行识别,在此基础上对反馈控制机制进行设计.以我国的住宅市场的价格运行系统为实证研究对象,结合历史数据对所构模型的有效性进行验证,并对未来可能出现情况进行预测.实证研究主要结论如下:第一,我国住宅市场投资者对预期收益的敏感程度以及供应商对商品前期价格的敏感程度均较高,价格运行能自发实现稳定的区域较小;第二,现有调控政策不变的情况下,我国住宅市场价格正向偏离稳定区域的程度将减小;第三,若政府从影响投资者心理预期的角度入手对我国住宅市场价格波动进行干预,希望我国住宅市场的价格运行能以最快的速度趋于稳态,则设计反馈控制机制时,应重视投资者对商品价格未来的心理预期受商品历史价格的影响程度远高于受市场供需的影响程度这一现象.     

PM2.5成因的逐步回归分析及治理方案研究

应用逐步回归分析方法获得了PM2.5与3个既与综合治理又与专项治理有关的因素SO_2、NO_2、PM10的最优二次回归方程,在将治理基准年与五年后目标的PM2.5浓度折算为对应的AQI指标之后,结合数据分析计算出了基准年的PM2.5、SO_2、NO_2、PM10这4个基准指标值.然后结合PM2.5综合治理与专项治理的费用经验公式,按照五年治理投入总经费最小的原则建立了一个标准的非线性规划模型,并求解出了最少的五年总投入经费及每年经费投入.对于指导PM2.5的治理工作有一定实际意义.     

与年龄相关的非线性种群系统的最优收获控制

讨论与年龄相关的一类非线性种群系统的最优收获控,运用泛函分析的Mazru's定理证明了最优收获控制的存在性,利用G-微分和Lions的变分不等式理论,导出了控制为最优的必要条件,得到了由积分-偏微分方程和变分不等式组成的最优性组,由最优性组确定最优控制.     

微机实时控制中的汉字开发

本文提出了在微机实时测量与控制中开发汉字的方法,给出了有关程序及流程图。要点是借助于 CCDOS 中的 CCLIB 库离线建立专用的小汉字库,使用时,完全不用任何 CCDOS 汉字系统来支持,大大节省内存空间,简而易行。特别适用于把汉字作为菜单提示或帮助的实时应用软件廉价开发。     

基于改进自适应混沌控制的逆可靠度分析方法

自适应混沌控制方法是一种高效、稳健的逆可靠度分析方法,但在求解强非线性凹功能函数时,计算效率仍然有待提高,且可能会陷入局部最优.通过对混沌控制因子更新策略进行改进,提出了基于改进自适应混沌控制的逆可靠度分析方法.数值算例分析表明:该方法能够有效地改善混沌控制因子自适应选取时的合理性,具有更好的收敛性和更高的计算效率,为结构可靠度分析和可靠度优化问题提供了更加高效、稳健的求解途径.     

Robust adaptive synchronization of uncertain complex networks with multiple time‐varying coupled delays

In this article, the synchronization problem of uncertain complex networks with multiple coupled time‐varying delays is studied. The synchronization criterion is deduced for complex dynamical networks with multiple different time‐varying coupling delays and uncertainties, based on Lyapunov stability theory and robust adaptive principle. By designing suitable robust adaptive synchronization controllers that have strong robustness against the uncertainties in coupling matrices, the all nodes states of complex networks globally asymptotically synchronize to a desired synchronization state. The numerical simulations are given to show the feasibility and effectiveness of theoretical results. © 2014 Wiley Periodicals, Inc. Complexity 20: 62–73, 2015