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Acta Mechanica Sinica 2011年第6期27卷 1052-1058页

作者： qing-Yun wang Yan-Hong Zheng Department of Dynamics and Control Beihang University 100191 Beijing China School of Mathematics and Computer Science Fujian Normal University 350007 Fuzhou China

In this paper,we investigate the evolution of spatiotemporal patterns and synchronization transitions in dependence on the information transmission delay and ion channel blocking in scale-free neuronal *** the underlying model of neuronal dynamics,we use the Hodgkin-Huxley equations incorporating channel blocking and intrinsic *** is shown that delays play a significant yet subtle role in shaping the dynamics of neuronal *** particular,regions of irregular and regular propagating excitatory fronts related to the synchronization transitions appear intermittently as the delay ***,the fraction of working sodium and potassium ion channels can also have a significant impact on the spatiotemporal dynamics of neuronal *** the fraction of blocked sodium channels increases,the frequency of excitatory events decreases,which in turn manifests as an increase in the neuronal synchrony that,however,is dysfunctional due to the virtual absence of large-amplitude ***,we also show that larger coupling strengths improve synchronization irrespective of the information transmission delay and channel *** presented results are also robust against the variation of the network size,thus providing insights that could facilitate understanding of the joint impact of ion channel blocking and information transmission delay on the spatiotemporal dynamics of neuronal networks.

关键词： Scale-free neuronal networks - Information transmission delay Ion channel blocking Synchronization

A systematic method of smooth switching LPV controllers design for a morphing aircraft

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Chinese Journal of Aeronautics 2015年第6期28卷 1640-1649页

作者： Jiang Weilai Dong Chaoyang wang qing School of Aeronautic Science and Engineering Beihang University School of Automation Science and Electrical Engineering Beihang University

This paper is concerned with a systematic method of smooth switching linear parameter- varying （LPV） controllers design for a morphing aircraft with a variable wing sweep angle. The morphing aircraft is modeled as an LPV system, whose scheduling parameter is the variation rate of the wing sweep angle. By dividing the scheduling parameter set into subsets with overlaps, output feedback controllers which consider smooth switching are designed and the controllers in over- lapped subsets are interpolated from two adjacent subsets. A switching law without constraint on the average dwell time is obtained which makes the conclusion less conservative. Furthermore, a systematic algorithm is developed to improve the efficiency of the controllers design process. The parameter set is divided into the fewest subsets on the premise that the closed-loop system has a desired performance. Simulation results demonstrate the effectiveness of this approach.

关键词： Morphing aircraft Parameter set division:Robust control Smooth switching Switched linear parameter-varying system

Time-varying formation tracking control of high-order multi-agent systems with multiple leaders and multiplicative noise

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Science China(Information Sciences) 2024年第12期67卷 191-207页

作者： Ruru JIA Xiaofeng ZONG qing wang College of Artificial Intelligence Nankai University School of Automation China University of Geosciences Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems School of Automation Science and Electrical Engineering Beihang University

This work discusses the time-varying formation(TVF) tracking control problem of high-order multi-agent systems(MASs) with multiple leaders and multiplicative measurement noise. With the help of Lyapunov function tools and stochastic analysis methods, the TVF tracking protocol with multiple leaders and multiplicative noise is developed based on the relative state measurements, where followers are driven to realize the target TVF while tracking the convex combination formed by multiple leaders. Then, the TVF tracking problem is converted into the mean square asymptotic stability problem of a stochastic differential equation(SDE); sufficient conditions related to the control gains are given by stabilizing the corresponding stochastic system. Moreover, a TVF tracking algorithm is presented to outline the steps of protocol ***, the theoretical results are illustrated in terms of simulation examples.

关键词： multi-agent systems multiple leaders multiplicative measurement noise stochastic differential equation formation tracking control

同方期刊数据库

Constraining quantitatively the timing and process of continent-continent collision using magmatic record： Method and examples

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Science China Earth Sciences 2017年第6期60卷 1040-1056页

作者： ZHU DiCheng wang qing ZHAO ZhiDan State Key Laboratory of Geological Processes and Mineral Resources Institute of Earth Sciences China University of Geosciences Beijing 100083 China Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101 China

Based on the main driving force of plate motion(the slab pull force generated by the descent of the oceanic plate in subduction zones) and the three primary mechanisms for magma generation(adding fluid, increasing temperature, and decreasing pressure), the continent-continent collisional process has been divided into three stages, including initial collision, ongoing collision, and tectonic transition. These stages are characterized by normal calc-alkaline andesitic magma(dehydration of the oceanic crust to release fluids), the migration of calc-alkaline magma toward the trench(dehydration of the oceanic crust or an increase in temperature) or small-scale crust-derived peraluminous magma(heat from intra-crustal shearing), and extensive magmatism with compositional diversity induced by slab break-off(increasing temperature and decreasing pressure), *** the basis of the obtained age of slab break-off, the timing of the initial continent-continent collision can be quantitatively back-dated using the convergence rate, depth of slab break-off, and subduction angle. The spatio-temporal migration of the magmatic activity of the Gangdese Batholith, the onset of magmatic flare-up, and the increase of magma temperature at 52–51Ma documented by the volcanic rocks of the Linzizong Pana Formation were most likely the result of the break-off of the Yarlung-Zangbo Neo-Tethyan oceanic lithosphere at approximately 53 Ma. This proposed age of slab break-off suggests that the initial India-Asia collision likely occurred at approximately 55–54 Ma, which is consistent with the collision ages constrained by other abundant geological data(60–55 Ma). This magmatic method has been applied to the Bitlis orogenic belt in southern Turkey in the Arabia-Eurasia continental collision zone, yielding an age range of approximately 29–22 Ma for the initial Arabia-Asia continental collision that is close to the collision ages recently obtained by apatite fission-track dating(approximately2

关键词： Magmatic record Slab break-off Timing of initial collision India-Asia collision Tethyan orogenic belt

Switching disturbance rejection attitude control of near space vehicles with variable structure

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Journal of Systems Engineering and Electronics 2019年第1期30卷 167-179页

作者： GONG Ligang wang qing DONG Chaoyang School of Automation Science and Electrical Engineering Beihang University School of Aeronautic Science and Engineering Beihang University

A switching disturbance rejection attitude control law is proposed for a near space vehicle(NSV) with variable *** multiple flight modes, system uncertainties and disturbances of the NSV are taken into account based on switched nonlinear systems. Compared with traditional backstepping design methods,the proposed method utilizes the added integrals of attitude angle and angular rate tracking errors to further decrease the tracking errors. Moreover, to reduce the computation complexity, a rapid convergent differentiator is employed to obtain the derivative of the virtual control command. Finally, for disturbance rejection, based on the idea from the extended state observer(ESO), two disturbance observers are designed by using non-smooth functions to estimate the disturbances in the switched nonlinear systems. All signals of the closed-loop system are proven to be uniformly ultimately bounded under the Lyapunov function framework. Simulation results demonstrate the effectiveness of the proposed control scheme.

关键词： near space vehicle (NSV) variable structure switched nonlinear system extended state observer (ESO).

Robust fault detection and optimization for a network of unmanned vehicles with imperfect communication channels

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Chinese Journal of Aeronautics 2014年第1期27卷 65-75页

作者： Niu Erzhuo wang qing Dong Chaoyang School of Automation Science and Electrical Engineering Beihang University School of Aeronautical Science and Engineering Beihang University

The observer-based robust fault detection and optimization for a network of unmanned vehicles with imperfect communication channels and norm bounded modeling uncertainties are addressed. The network of unmanned vehicles is modeled as a discrete-time uncertain Markovian jump system. Based on the model, a residual generator is constructed and the sufficient condition for the existence of the desired fault detection filter is derived in terms of linear matrix inequality. Furthermore, a time domain optimization approach is proposed to improve the performance of the fault detection system. The problem of detecting small faults can be formulated as an optimization problem and its solution is given. For preventing false alarms, a new adaptive threshold function is established. The combined fault detection and optimization algorithm and the adaptive threshold are then applied to a network of highly maneuverable technology vehicles to illustrate the effective- ness of the orooosed aooroach.

关键词： Fault detection andoptimization Imperfect communicationchannel Network Uncertainty Unmanned vehicle

A CASE STUDY FOR ADVANCED PLANNING AND SCHEDULING (APS)

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Journal of Systems Science and Systems Engineering 2011年第4期20卷 460-474页

作者： Kejia CHEN Ping Jl qing wang School of Management Fuzhou University Fuzhou 350108 China Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong Department of Systems Engineering Northeastern University Shenyang 110819 China

This paper presents a case study for the advanced planning and scheduling （APS） problem encountered in a light source manufacturer. The APS problem explicitly considers due dates of products, operation sequences among items, and capacity constraints of the manufacturing system. The objective of the problem is to seek the minimum cost of both production idle time and tardiness or earliness penalty of an order. An intelligent heuristic is applied to the problem, and the results demonstrate that significant production performances can be achieved while ensuring customer satisfaction as opposed to normal oractices followed in the company relying on human expertise.

关键词： Advanced planning and scheduling case study intelligent heuristic

Assessment of structural damage using natural frequency changes

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Acta Mechanica Sinica 2012年第1期28卷 118-127页

作者： Shu-qing wang Hua-Jun Li Department of Ocean Engineering Ocean University of China266100 QingdaoChina

The present paper develops a new method for damage localization and severity estimation based on the employment of modal strain energy. This method is able to determine the damage locations and estimate their severities, requiring only the information about the changes of a few lower natural frequencies. First, a damage quantification method is formulated and iterative approach is adopted for determining the damage extent. Then a damage localization algorithm is proposed, in which a damage indicator is formulated where unity value corresponds to the true damage scenario. Finally, numerical studies and model tests are conducted to demonstrate the effectiveness of the developed algorithm.

关键词： Damage assessment Damage detection Strain energy - Modal analysis - Natural frequency

Aerodynamic shape optimization for alleviating dynamic stall characteristics of helicopter rotor airfoil

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Chinese Journal of Aeronautics 2015年第2期28卷 346-356页

作者： wang qing Zhao Qijun Wu Qi National Key Laboratory of Science and Technology on Rotorcraft Aeromechanics Nanjing University of Aeronautics and Astronautics

In order to alleviate the dynamic stall effects in helicopter rotor, the sequential quadratic programming （SQP） method is employed to optimize the characteristics of airfoil under dynamic stall conditions based on the SC1095 airfoil. The geometry of airfoil is parameterized by the class-shape-transformation （CST） method, and the C-topology body-fitted mesh is then automati- cally generated around the airfoil by solving the Poisson equations. Based on the grid generation technology, the unsteady Reynolds-averaged Navier-Stokes （RANS） equations are chosen as the governing equations for predicting airfoil flow field and the highly-efficient implicit scheme of lower-upper symmetric Gauss-Seidel （LU-SGS） is adopted for temporal discretization. To capture the dynamic stall phenomenon of the rotor more accurately, the Spalart-Allmaras turbulence model is employed to close the RANS equations. The optimized airfoil with a larger leading edge radius and camber is obtained. The leading edge vortex and trailing edge separation of the opti- mized airfoil under unsteady conditions are obviously weakened, and the dynamic stall character- istics of optimized airfoil at different Mach numbers, reduced frequencies and angles of attack are also obviously improved compared with the baseline SC1095 airfoil. It is demonstrated that the optimized method is effective and the optimized airfoil is suitable as the helicopter rotor airfoil.

关键词： Airfoil Computational fluiddynamics Dynamic stall Helicopter Optimization Rotor

A new calibration model for pointing a radio telescope that considers nonlinear errors in the azimuth axis

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Research in Astronomy and Astrophysics 2014年第6期14卷 733-740页

作者： De-qing Kong Song-Gen wang Jin-qing wang Min wang Hong-Bo Zhang National Astronomical Observatories Chinese Academy of Sciences College of Mechanical Engineering Hangzhou Dianzi University Shanghai Astronomical Observatory Chinese Academy of Sciences Yunnan Observatories Chinese Academy of Sciences

A new calibration model of a radio telescope that includes pointing error is presented, which considers nonlinear errors in the azimuth axis. For a large radio telescope, in particular for a telescope with a turntable, it is difficult to correct pointing errors using a traditional linear calibration model, because errors produced by the wheel-on-rail or center bearing structures are generally nonlinear. Fourier expansion is made for the oblique error and parameters describing the inclination direction along the azimuth axis based on the linear calibration model, and a new calibration model for pointing is derived. The new pointing model is applied to the 40 m radio telescope administered by Yunnan Observatories, which is a telescope that uses a turntable. The results show that this model can significantly reduce the residual systematic errors due to nonlinearity in the azimuth axis compared with the linear model.

关键词： telescopes - antennas - pointing models