Hybrid internal model control and proportional control of chaotic dynamical systems

INTRODUCTIONOneoftheoldestresearchesofchaosincon trolfieldscanbeseeninthepaperbyKalman(1956) ,whofirstfoundnon synchronousoscil lationsinatwo dimensionalsampled datacontrolsystem .IntheOGYmethoddevelopedbyOttetal.(1990 ) ,chaoticphenomenawaseliminatedbyadjustingparametersofthesystemswhenthechaoticorbitcomesnearaperiodicalorbit.ButtheOGY’smethodrequiresmonitoringthesys temlongenoughtodeterminealinearizationmodeintheneighborhoodofthedesiredunstableperiodicorbitbeforeitcanbeapplied .Besi…     

Sliding mode control for synchronization of chaotic systems with structure or parameters mismatching

INTRODUCTION Synchronization of chaotic systems and its ap-plication to secure communication has recently re-ceived much attention. Several chaos synchronization schemes have been successfully established (Liao and Huang, 1999; Jiang, 2002; Zhao et al., 2004). How-ever, to our best knowledge, most of the chaos syn-chronization strategies have been studied in similar oscillators. In fact, from the perspective of hardware implementation, the resistance and capacitance of the resistors and…     

企业货币资金内部控制：问题与建议

货币资金是企业资产的重要组成部分,由于货币资金具有高度的流动性和控制风险,企业在组织会计核算的过程中,加强货币资金的管理和控制,对于保障企业资产安全和完整,提高资金周转速度和使用效益,具有重要意义。本文列举了货币资金管理中一些常见的错弊行为,并通过对货币资金内部控制的目标、原则及影响货币资金内控环境的简单阐述和分析,着重提出如何加强货币资金的内部控制,从而确保经营管理活动合法有效。     

电算化会计系统下的内部控制

本文分析了当前国内企业电算化会计信息系统内部控制存在的问题,并针对这些问题提出了完善电算化会计内部控制体系的措施,以发挥会计电算化的高效、准确性,为企业的经营决策提供完整的信息,创造更高的效益。     

关于企业财务内部控制机制的探索

企业内部控制理论体系形成于20世纪60年代中期,70年代至今被西方发达企业所广泛运用。企业财务的内部控制体系作为企业内部控制体系的一个重要分支,在近半个世纪的发展中,为企业的资本运作带来了良好的经济效益。近年来,国内企业也相续引进企业财务内部控制机制,虽然该套管理体系尚处于雏形,但可以预见,随着企业竞争国际化趋势日益突显,企业财务内部控制的实施必然带来可观的效率和效益。     

Passive control of a class of chaotic dynamical systems with nonlinear observer

A passive control strategy with nonlinear observer is proposed, which can be used to control a class of chaotic dynamical systems to stabilize at different equilibrium points. If the nonlinear function of chaotic system satisfies Lipschitz condition, the nonlinear observer can observe the state variables of the chaotic systems. An important property of passive system is studied to control chaotic systems, that is passive system can be asymptotically stabilized by state feedback controller whose state variables are presented by nonlinear observer. Simulation results indicated that the proposed chaos control method is very effective in a class of chaotic systems.     

Determining heating pipe temperature in greenhouse using proportional integral plus feedforward control and radial basic function neural-networks

INTRODUCTION The objective of greenhouse environment controlis to create an ideal climatic condition for plant growth.The interior air temperature is the most importantcontrol factor. Generally, heating facilities must beinstalled in the greenhouse in order to make the inte-rior air meet the need of the crop in cold days. Hotwater heating is the prevailing method. In order tosave energy, precise temperature control is necessary(Chalabi et al., 1996). For precise control of interior…     

谈税务策划与内部会计控制

税务筹划与内部会计控制两者在某种程度上有互相联系和互相推动的作用,本文旨在针对企业经营过程中在这两方面都依然十分薄弱的现状,通过寻找到两者的契合点,能够使企业强化内部会计控制和税务策划的意识,并充分发挥内部会计控制和实行税收策划的实际优势,实行在有限的成本下寻找能解决问题最优方法的新的探索.     

一类描述方体Cantor集上的混沌映射的拟移位映射

引进n维单边符号空间，并在其上定义移位映射和拟移位映射．得到这两类映射的混沌性以及共轭关系．并用拟移位映射描述了方体Cantor集上的混沌映射．     

基于神经网络的伺服系统辨识与内模控制

根据一组伺服驱动系统的辨识试验数据，进行了基于神经网络的非线性系统的正模型与逆模型辨识，分析了辨识结果，给出基于神经网络模型的内模控制方案，并提出了实现高速高精运动的可能方式。     

基于自适应控制的混沌系统分时同步

讨论混沌系统的分时同步.通过设计控制策略实现了一个混沌系统的一个分量对另一个混沌系统的任一分量的分时跟踪同步,并且在同步的过程中,系统的参数也被识别.最后仿真结果表明了该方法的有效性.     

内部控制制度制定的目标模式--政府与市场分析

内部控制制度可以由政府或市场来供给。利用交易费用理论,针对我国的具体国情,对我国内部控制制度制定模式应以政府模式为基调,适当引入市场规则。     

Hybrid event based control architecture for tele-robotic systems controlled through Internet

INTRODUCTIONWiththerapiddevelopmentofInternettech-nology,moreandmoreInternetbasedapplicationsinindustrieshavebeenbroughtforth,rangingfromwebbaseddataacquisition(Huetal.,2002)torobotssharingthroughtheInternet(Safaricetal.,1999).Inrecentyears,manyscientistsandengi-neershavedevotedenthusiasticallymuchtimetostudyofInternetbasedtele-roboticsystems(BradyandTarn,2001).Internet,asachannelofcommu-nication,providesanewmediaforcontrolsignalsandsensoryinformationdeliverycontrollablethroughtheInter…     

Hybrid event based control architecture for tele-robotic systems controlled through internet

A new hybrid event based control architecture for tele-robotic systems controlled through the Internet is proposed in this paper. Different from the traditional event based control method, the new framework does not require every part of the system to be strictly event synchronized. Instead, it allows time referenced control components to be integrated into this framework, which makes it more convenient to develop Internet based control systems. Since there are two reference variables, time and event, in this architecture, how to coordinate these components with different references to keep the stability of the whole system is discussed in detail in this paper. To verify this new idea, an experiment was conducted to control the end effector of a PUMA robot tracking a continuous state trajectory given on-line by the remote operator. Experimental results confirmed the stability of such systems being controlled through the Internet in real-time.     

Boiler-turbine control system design using continuous-time nonlinear model predictive control

A continuous-time nonlinear model predictive controller （NMPC） was designed for a boiler-turbine unit. The controller was designed by optimizing a receding-horizon performance index, with the nonlinear system approximated by its Taylor series expansion with a certain order, the magnitude saturation constraints on the inputs satisfied by increasing the predictive time, and the rate saturation conditions on the actuators satisfied by tuning the time constant of the reference trajectories in a reference governor. Simulation results showed that the controller can drive the drum pressure and output power of the nonlinear boiler-turbine unit to follow their respective reference trajectories throughout a varying operation range and keep the water level deviation within tolerances. Comparison of the NMPC scheme with the generic model control （GMC） scheme indicated that the responses are slower and there are more oscillations in the responses of the water level, fuel flow input and feed water flow input in the GMC scheme when the boiler-turbine unit is operating over a wide range.     

基于变周期采样模型的网络控制系统的随机最优状态反馈控制

本文研究变周期采样的网络控制系统模型的随机最优反馈控制。假设网络诱导延时服从某一个区间的均匀分布,设计一个依赖延时的状态反馈控制器,使得所建立的变周期采样的NCS模型指数均方稳定。利用动态规划思想结合Bellman方程通过优化所给定的性能指标,得到了随机最优反馈控制器设计方法,并通过仿真实例验证了本章提出方法的有效性。     

Robust model predictive control for discrete uncertain nonlinear systems with time-delay via fuzzy model

INTRODUCTION In recent years, research on nonlinear model predictive control has attracted significant attention because most practical processes are nonlinear. In industry process control, model predictive controllers based on linear models (LMPC) are often used to control nonlinear systems. When the operating con- ditions undergo significant changes, the performance of LMPC can deteriorate drastically. Under such conditions, predictive control based on nonlinear models (NMPC) shoul…     

带死区非线性输入的未知混沌系统控制

针对具有死区非线性输入的未知混沌系统的控制问题,基于Lyapunov稳定性理论建立变结构模糊自适应控制器及系统参数的自适应规则。控制器的设计过程中无需知道未知非线性未知函数的上界及非线性控制输入的增益衰减度,该方法能有效消除死区非线性输入对系统的影响,并能保证闭环系统所有信号一致有界,跟踪误差渐近收敛到原点的一个可调邻域内。数值仿真的结果也验证了该方法的有效性。     

Predictive control of a direct internal reforming SOFC using a self recurrent wavelet network model

In this paper, an application of a nonlinear predictive controller based on a self recurrent wavelet network （SRWN） model for a direct internal reforming solid oxide fuel cell （DIR-SOFC） is presented. As operating temperature and fuel utilization are two important parameters, the SOFC is identified using an SRWN with inlet fuel flow rate, inlet air flow rate and current as inputs, and temperature and fuel utilization as outputs. To improve the operating performance of the DIR-SOFC and guarantee proper operating conditions, the nonlinear predictive control is implemented using the off-line trained and on-line modified SRWN model, to manipulate the inlet flow rates to keep the temperature and the fuel utilization at desired levels. Simulation results show satisfactory predictive accuracy of the SRWN model, and demonstrate the excellence of the SRWN-based predictive controller for the DIR-SOFC.     

Passive control of Permanent Magnet Synchronous Motor chaotic systems

Permanent Magnet Synchronous Motor model can exhibit a variety of chaotic phenomena under some choices of system parameters and external input. Based on the property of passive system, the essential conditions were studied, by which Permanent Magnet Synchronous Motor chaotic system could be equivalent to passive system. Using Lyapunov stability theory, the convergence condition deciding the system's characters was discussed. In the convergence condition area, the equivalent passive system could be globally asymptotically stabilized by smooth state feedback.