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Nonlinear asymptotic attitude tracking control of an underactuated 3-degree-of-freedom helicopter using neural network feedforward term

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控制理论与应用（英文版） 2013年第3期11卷 428-435页

作者： Xiang LIU Bin XIAN Jianchuan GUO Bo ZHAO chen diao Institute of Robotics and Autonomous System Tianjin Key Laboratory of Process Measurement and Control and School of Electrical Engineering and Automation Tianjin University

This paper proposes a new asymptotic attitude tracking controller for an underactuated 3-degree-of-freedom （DOF） laboratory helicopter system by using a nonlinear robust feedback and a neural network （NN） feedforward term. The nonlinear robust control law is developed through a modified inner-outer loop approach. The application of the NN-based feedforward is to compensate for the system uncertainties. The proposed control design strategy requires very limited knowledge of the system dynamic model, and achieves good robustness with respect to system parametric uncertainties. A Lyapunov-based stability analysis shows that the proposed algorithms can ensure asymptotic tracking of the helicopter＇s elevation and travel motion, while keeping the stability of the closed-loop system. Real-time experiment results demonstrate that the controller has achieved good tracking performance.

关键词： 3-DOF helicopter Nonlinear Robust control Asymptotic tracking

New Proper Reparameterization of Plane Rational Bézier Curves

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Journal of Computer Science & Technology 2024年第5期39卷 1193-1206页

作者： Zhen-Fei Wang Xiao-diao chen Jun-Hai Yong School of Computer Hangzhou Dianzi UniversityHangzhou 310018China Haihe Laboratory of Information Technology Application Innovation Tianjin 300480China School of Software Tsinghua UniversityBeijing 100084China

Coincidence detection of two curves or two surfaces has wide application in computer-aided design(CAD)and computer-aided geometric design(CAGD).Proper reparameterization is the most complicated part in the *** paper presents and proves the efficient and necessary coincidence condition for two rational Bézier curves in a new *** also proposes an effective and efficient proper reparameterization method,Algorithm 1,for detecting a rational Bézier curve which can be degenerated into a new one of a lower degree.A numerical proper reparameterization method,Algorithm 2,and examples are also *** 1 is up to ten times faster than other prevailing methods,and Algorithm 2 is twice as fast and half as close as other prevailing *** CAD systems using Algorithm 1 and Algorithm 2 will hold accuracy and little computation time.

关键词： rational Bézier curve coincidence condition control polygon degeneration proper reparameterization

An Index to Measure Controllability of Complex Networks 36

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An Index to Measure Controllability of Complex Networks

第36届中国控制会议

作者： TAN,Zong-Yuan CAI,Ning diao,chen GUO,Ling College of Electrical Engineering Northwest Minzu University

ISBN: (纸本)9781538629185

The main topic of this paper is the controllability of dynamic complex *** our current study,an index is selected for the sake of quantitatively measuring the controllability of *** influence of this index is mainly analyzed according to empirical researches on two classes of network structures,for instance,stochastic networks and small-world *** such an index,the comparison of controllability between different types of network structures could be possible.

关键词： Controllability Complex Network Quantitative Measure

Efficient Synthesis of Highly Optically Active Quaternary Oxindoles

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Efficient Synthesis of Highly Optically Active Quaternary Ox...

手性中国2014学术研讨会

作者： diao chen Ming-Hua Xu State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of Sciences

The optically active 3-disubstituted oxindoles are commonly found in a large family of natural products and biologically active compounds[1].Among them,the tetrasubstituted 3-aminooxindoles and3-hydroxyoxindoles have been recognized as important core structures of bioactive molecules and drug ***,our group has been succeeded on the synthesis of highly optically pure3-ally-3-aminooxindoles[2]and 3-aryl-3-hydroxyoxindoles using N-tert-butanesulfinyl imine chemistry and chiral sulfur-olefin catalysis.[3]In continuation of our interest in this field,we attempted to develop versatile approaches to access diverse quaternary carbon-containing ***,we present our new achievements on challenging diastereoselective cyanation as well as trifluoromethylation of isatin ketimines,[4a]and enantioselective direct arylation of isatins,[4b]allowing construction of various tetrasubstituted 3-aminooxindoles and 3-hydroxyoxindoles in highly enantiomerically enriched forms.

关键词： Cyanation Trifluoromethylation Arylation 3-aminooxindoles 3-hydroxyoxindoles.

Amplification Effect of Peak Ground Motion Acceleration in ClassⅡ and Ⅲ Sites over Shandong Province

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Earthquake Research in China 2011年第4期25卷 498-506页

作者： diao Ting chen Shijun Jiang Zaofeng Shandong Institute of Earthquake Engineering Jinan 250021 China

In this paper, the amplification factor （ks ） of peek ground motion with different exceedance probability in class Ⅱ and Ⅲ sites over Shandong Province was estimated by analyzing the seismic response data of soil layers collected from 358 boreholes of class Ⅱ sites and 140 boreholes of class Ⅲ site. From the results, one can conclude that：（1） The scatter plot of ks generally obeys a normal distribution ; （2） ks decreases with the increase of the strength of input ground motion, which is more apparent in Class Ⅲ site than in class lI site; （3） for class Ⅱ site, with the increase of depth of the bedrock interface where ground motion inputs, ks increases gradually until to a stable value when the depth reaches up to approximately 20 meters or larger. Yet, for class Ⅲ site, ks is insensitive to the depth; （4） the average of ks for class Ⅱ site is 1.47, slightly larger than that used in the Seismic Ground Motion Parameters Zonation Map of China （ GB 18306-2001 ）. Also, ks in class Ⅱ and Ⅲ sites at different levels of peak ground acceleration over Shandong Province is preliminarily discussed in the paper.

关键词： Seismic ground motion Peak ground acceleration Site condition Exceedanceprobability amplification factor

A Novel Data Fusion Algorithm for Multivariate Time Series

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A Novel Data Fusion Algorithm for Multivariate Time Series

第30届中国控制与决策会议

作者： chen diao Bin Wang Ning Cai School of Electrical Engineering Northwest Minzu University MOE Key Laboratory of China's National Linguistic Information Technology

In this paper, a novel fusion data algorithm is proposed. In the method, multi-lead ECG signals are appropriately converted to a single-lead physiological signal via the idea of the local weighted linear prediction al... 详细信息

关键词： ECG signal Quality assessment Data fusion

On Optimization Technology in 4G System

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On Optimization Technology in 4G System

第30届中国控制与决策会议

作者： Jin Jin chen diao Ning Cai College of Electrical Engineering Northwest Minzu University MOE Key Laboratory of China's National Linguistic Information Technology

With the development of wireless communication technology, the fourth generation(4 G) mobile system research is still the focus. In modern heterogeneous 4 G wireless networks, the basic standard is call service interrupt call and call continuity. Switching is the best way to achieve continuous call service. In heterogeneous wireless networks, the key challenge is continuous call connections between different networks such as Wi-Fi, Wi-Max, WLAN, and CDMA. At present, the concept of cellular mobile communication system is introduced in this paper, and the last link of cellular network or mobile network is wireless communication. The internet. The network is distributed over a land area called a cell, each serving at least one fixed location transceiver called a cell site or a base station. The concept of handover is then described in detail, which is the process of transferring an ongoing call or data session from one channel connected to the core network to another channel. Switching technology is divided into hard switching and soft switching, compared with the traditional switching(hard switching, etc.), soft switching has many advantages: it improves the seamless communication, soft switching is the main feature of the transmission is not interrupted. However, soft handoffs also have some drawbacks, such as increasing complexity and consuming additional resources in the downstream direction. Finally, this paper discusses various switching decision algorithms and analyzes their performance. The performance of one of the 4 G vertical switching algorithms is studied and simulated. The results of the analysis and the results show that the proposed algorithm gives better results in minimizing the processing delay during the switching process.

关键词： communication system Switching technology Cell Vertical switching algorithm

Modeling and Analysis of a Type of Quadrupole Magnet Power Supply

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Modeling and Analysis of a Type of Quadrupole Magnet Power S...

第37届中国控制会议

作者： Bin Wang chen diao Ning Cai School of Electrical Engineering Northwest Minzu University Key Laboratory of China's Ethnic Languages and Information Technology of Ministry of Education

Quadrupole magnet power supply designing is vital for magnetic field system in the development of accelerator. Modeling and analysis of quadrupole magnet power supply is helpful for designing. The topology of the main circuit of synchrotron quadrupole magnet power supply system is analyzed followed by the control strategy in the paper. Modeling of each link and frequency response of transfer function both from duty ratio to output voltage and from duty ratio to the load current are given to validate the modeling and analysis.

关键词： Modeling Quadrupole magnet power supply PWM control

Robust tracking control design for a flexible air-breathing hypersonic vehicle

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Journal of Central South University 2014年第1期21卷 130-139页

作者：张垚鲜斌刁琛赵勃郭建川 Institute of Robotics and Autonomous System Tianjin Key Laboratory of Process Measurement and ControlSchool of Electrical Engineering and AutomationTianjin University

A nonlinear robust controller was presented to improve the tracking control performance of a flexible air-breathing hypersonic vehicle(AHV) which is subjected to system parametric uncertainties and unknown additive time-varying *** longitudinal dynamic model for the flexible AHV was used for the control ***-gain observers were designed to compensate for the system uncertainties and additive *** gain theorem and Lyapunov based stability analysis were utilized to prove the stability of the closed loop *** uniformly ultimately bounded tracking of the vehicle's velocity,altitude and attack angle were achieved under aeroelastic effects,system parametric uncertainties and unknown additive ***/Simulink simulation results were provided to validate the robustness of the proposed control *** simulation results demonstrate that the tracking errors stay in a small region around zero.

关键词： hypersonic vehicles nonlinear robust control flexible mode small gain theorem Lyapunov