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一种改进的蚁群算法用于灰色约束非线性规划问题求解

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四川大学学报（自然科学版） 2004年第5期41卷 973-977页

作者：段海滨王道波于秀芬朱家强南京航空航天大学自动化学院南京210016 中国科学院空间科学与应用研究中心北京100080 清华大学智能技术与系统国家重点实验室北京100084

针对灰色约束非线性规划问题,设计了一种改进蚁群算法.该算法采用了正反馈机制,在对灰色约束非线性规划问题白化处理后,将罚函数方法引入到目标函数中,同时给出了改进蚁群算法的仿真流程.实例应用表明,将改进后的蚁群算法应用于灰色约... 详细信息

针对灰色约束非线性规划问题,设计了一种改进蚁群算法.该算法采用了正反馈机制,在对灰色约束非线性规划问题白化处理后,将罚函数方法引入到目标函数中,同时给出了改进蚁群算法的仿真流程.实例应用表明,将改进后的蚁群算法应用于灰色约束非线性规划问题的求解是可行有效的.

关键词：灰色系统灰色约束非线性规划问题蚁群算法信息素

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基于FCS的高速并行超声信号采集系统

无损检测 2009年第8期31卷 639-642页

作者：孙志林石峥映梅劲松包亚萍南京工业大学信息科学与工程学院南京210009 南京拓控信息科技有限公司南京210019 南京航空航天大学自动化学院南京210016

为了实现机车、车辆和动车组等车轮的自动化在线探伤,提出一种通过式压电超声波在线探伤方案。设计了基于FCS(现场总线控制系统)的100 MHz采样率并行超声信号采集系统。该系统充分利用车轮通过式在线探伤中顺序采样的工作特点,采用时分... 详细信息

为了实现机车、车辆和动车组等车轮的自动化在线探伤,提出一种通过式压电超声波在线探伤方案。设计了基于FCS(现场总线控制系统)的100 MHz采样率并行超声信号采集系统。该系统充分利用车轮通过式在线探伤中顺序采样的工作特点,采用时分复用单通道多机并行技术,提高了高速A/D的利用率和各通道的一致性。多采样率可去除冗余数据,提高系统的处理效率。所用缺陷信号的后续处理模式提高了缺陷定性定量识别的可靠性。

关键词：超声波检测在线自动化探伤系统设计高速数据采集多采样率

Three vortex motion in the slightly viscous flow

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Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 735-744页

作者： ZHU Hao & CHENG KeMing college of Aerospace engineering, nanjing university of aeronautics and astronautics, nanjing 210016, china 1. college of Aerospace engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

The dynamics of three vortices moving in an ideal fluid in a plane can be expressed in Hamiltonian form. However, when viscosity can not be ignored, the system of point vortices has not this delicious structure. This investigation focuses on the viscosity effect on the motion of three vortices. Since the viscous diffusion of vortices is simulated by Brownian motion, the equations of intervortical distances are obtained by Ito formula. These equations show that there exist two viscosity effects on intervortical distances: stable expansion and random impulse. Furthermore, via employing the asymptotic solution to these equations, these two viscous effects have been shown to destroy the self-similar process of collapse and make it into a new configuration, which is similar to the near collapse in the ideal case.

关键词： point vortex slightly viscous flow Fokker-Planck equation collapse Ito formula

Adaptive recurrent-functional-link-network control for hypersonic vehicles with atmospheric disturbances

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Science china(Information Sciences) 2011年第3期54卷 482-497页

作者： DU YanLi 1, WU QingXian 2 , JIANG ChangSheng 2 & XUE YaLi 2 1 college of astronautics, nanjing university of aeronautics and astronautics, nanjing 210016, china 2 college of automation engineering, nanjing university of aeronautics and astronautics, nanjing 210016, china 1. college of astronautics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China2. College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

The controller design for a near-space hypersonic vehicle (NHV) is challenging due to its plant uncertainties and sensitivity to atmospheric disturbances such as gusts and turbulence. This paper first derives 12 states equations of NHVs subjected to variable wind field, and presents a novel recurrent neural network (RNN) control method for restraining atmospheric disturbances. The method devises a new B-spline recurrent functional link network (BRFLN) and combines it with the nonlinear generalized predictive control (NGPC) algorithm. Moreover, the proportional-derivative (PD) correction BRFLN is proposed to approximate atmo- spheric disturbances in flight. The weights of BRFLN are online tuned by the adaptive law based on Lyapunov stability theorem. Finally, simulation results show a satisfactory performance for the attitude tracking of the NHV in the mesosphere, and also illustrate the controller's robustness to wind turbulence.

关键词： near-space hypersonic vehicle atmospheric disturbances nonlinear predictive control adaptive control B-spline recurrent functional link network

Design of longitudinal predictive re-entry guidance law based on variable universe fuzzy-PI composite control

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控制理论与应用（英文版） 2012年第2期10卷 264-267页

作者： Yin WANG 1 , Yuping LU 2 1.college of automation engineering, nanjing university of aeronautics and astronautics, nanjing Jiangsu 210016, china 2.college of astronautics, nanjing university of aeronautics and astronautics, nanjing Jiangsu 210016, china college of automation engineering Nanjing University of Aeronautics and Astronautics Nanjing Jiangsu China college of astronautics Nanjing University of Aeronautics and Astronautics Nanjing Jiangsu China

This paper studies the longitudinal predictive re-entry guidance law based on the variable universe fuzzy- PI composite control to overcome the inaccuracy of the reference trajectory re-entry guidance for reentry vehicles. The variable universe fuzzy controller is used to obtain a satisfactory dynamic response when the downrange error is large, and the PI controller is utilized to eliminate the steady state error when the downrange error is small. Simulation results show that the proposed guidance law is very robust to the initial errors and can achieve better accuracy, and is also able to handle the effect of the stochastic errors in re-entry processes.

关键词： Re-entry guidance Variable universe Fuzzy control PI control

Online-SVR-compensated nonlinear generalized predictive control for hypersonic vehicles

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Science china(Information Sciences) 2011年第3期54卷 551-562页

作者： CHENG Lu , JIANG Chang Sheng & PU Ming college of automation engineering, nanjing university of aeronautics and astronautics, nanjing 210016, china 1. college of automation engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

This paper is concerned with the problem of hypersonic vehicle (HSV) attitude control system in uncertain flight conditions. The problem can be expressed as the adaptive robust control for a class of uncertain nonlinear systems. Based on the description of the aerodynamic structure and the model of flight control system of a certain kind of HSV, the ideal nonlinear generalized predictive control (NGPC) law based on uncertain nonlinear model is raised first to optimize the receding-horizon criterion of tracking errors. Then the online support vector regression (SVR) is employed to identify the uncertain item in the ideal control law. It is the compensating part of the controller. In addition, the stability of the close-loop system is analyzed using the Lyapunov method. The developed control strategy is well-implemented in this HSV attitude control system, and the simulation results compared with both nominal NGPC and RBF neural network disturbance observer show the good robustness and disturbance attenuation ability of this strategy and demonstrate the efficiency of online SVR algorithm.

关键词： hypersonic vehicle flight control nonlinear generalized predictive control online support vector regression

Partial discharge-induced crack growth in dielectric materials

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Science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 886-891页

作者： LUO JiaCheng,GAO CunFa & DAI XiangHua college of Aerospace engineering,nanjing university of aeronautics & astronautics,nanjing 210016,china 1. college of Aerospace engineering Nanjing University of Aeronautics & Astronautics Nanjing 210016 China

Partial discharge(PD) of an air-filled semi-permeable crack in a dielectric material is studied based on the streamer-type discharge mechanism to explore the effects of applied mechanical-electric fields on crack *** the frame of two-dimensional deformation,the electric field inside the crack is first derived by taking the crack deformation into ***,the effects of electric field before PD are discussed through considering the contribution of the induced electric field inside the deformed crack space to the total energy release ***,PD and its effects on crack growth are *** is found that:(1) before PD,the applied electric field always retards crack growth;(2) during PD,the applied electric field can induce crack growth in dielectric materials.

关键词： crack dielectric materials partial discharge electric field effects

Resolution method for overlapping peaks based on the fractional-order differential

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Science china Chemistry 2007年第6期50卷 797-805页

作者： LI YuanLu1, YU ShengLin2 & ZHENG Gang2 1 college of Information & Control, nanjing university of Information Science & Technology, nanjing 210044, china 2 college of automation engineering, nanjing university of aeronautics and astronautics, nanjing 210016, china 1. college of Information & Control Nanjing University of Information Science & Technology Nanjing 210044 China 2. college of automation engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Equations between the differential order and the maximum of the fractional-order differential for the specified peak signals are developed based on the variation of the maximum of the specified peak signals at different orders. Also, equations between the differential order and the zero-crossing of the fractional-order differential of the specified peak signals are proposed according to the variation of the zero-crossing of the specified peak signals at different orders. Characteristic paramters of the Gaus- sian peak, Lorentzian peak, and Tsallis peak can be estimated using estimator I and estimator II which are obtained by the equations above. As a result, a new method is presented to resolve the overlapped peaks signal. Firstly, a fractional-order differential of the specified peak signals is obtained with the fractional-order differentiation filter. Then, characteristic paramters of the specified peak signals can be extracted using estimator I and estimator II. Finally, the Tsallis peak is used as a model to assign the overlapping peak signals correctly. Experimental results show that the proposed method is efficient and effective for the simulated overlapping peaks and detected overlapping voltammetric peak signals.

关键词： fractional-order differentiation filter, fractional-order differential, overlapping peaks, voltammetric peak

On the general expressions of finite Hankel transform

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Science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2125-2130页

作者： JIANG Quan 1,2 & GAO CunFa 1 1 college of Aerospace engineering,nanjing university of aeronautics and astronautics,nanjing 210016,china 2 School of Civil engineering,Nantong university,Nantong 226019,china 1. college of Aerospace engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China2. School of Civil Engineering Nantong University Nantong 226019 China

The general expressions of finite Hankel transform are naturally deduced with the help of the property of Bessel *** equations in this paper can degenerate into three kinds of boundaries since all the coefficients in the boundary conditions are taken into *** results can be adopted in solving physics problems involving the finite Hankel transform.

关键词： hankel transform bessel function finite integral