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4th World Congress on Intelligent Control and Automation

作者： Liu, TN Guan, XZ Liu, ZY Xie, AH Zhang, H Daqing Petr Inst Dept Automat & Control Engn Anda 151400 Heilongjiang Peoples R China

ISBN: (纸本)0780372689

In this paper, it is framed a model of RBF neural network (RBFNN) to solve identification of nonlinear systems. First, it is proposed a kind of optimal selection cluster algorithm. By this algorithm, it is optimally gained the hidden layer node number of RBFNN in terms of input samples. At the same time, it is obtained the initial parameters values of RBF. Then, it is estimated the parameters value of RBF by gradient algorithm with momentum terms, and identified the weights of RBFNN by recursive least square algorithm. With the above two algorithms, it is alternately iterated. By the above hybrid algorithms, it is not only raised identification precision of RBFNN, but also improved generalization property of the net. It is proved the validity of the scheme by its applications.

关键词： RBF neural network optimal selection cluster algorithm identification gradient algorithm recursive least square algorithm

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Stabilization of stochastic systems with hidden Markovian jumps

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Science in China(Series F) 2001年第2期44卷 104-118页

作者：黄民懿郭雷 Institute of Systems Science Chinese Academy of Sciences Beijing China

This paper considers the adaptive control of discrete-time hybrid stochastic systems with unknown randomly jumping parameters described by a finite-state hidden Markov chain. An intuitive yet longstanding conjecture in this area is that such hybrid systems can be adaptively stabilized whenever the rate of transition of the hidden Markov chain is small enough. This paper provides a rigorous positive answer to this conjecture by establishing the global stability of a gradient-algorithm-based adaptive linear-quadratic control.

关键词： stochastic adaptive control Markovian jump parameters gradient algorithm stability linear quadratic control.

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Edge Detection in Potential Fields Using Optimal Auto-Ratios of Vertical gradients

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Chinese Journal of Geophysics 2014年第6期56卷 766-776页

作者： WANG Yan-Guo ZHANG Feng-Xu LIU Cai WANG Zhu-Wen ZHANG Jin College of Nuclear Engineering and Geophysics East China Institute of Technology Nanchang 330013 China College of Geo-Exploration Science and Technology Jilin University Changchun 130026 China

Derivative calculation of potential-fields is widely used in edge detection of geologic bodies. However, the traditional gradient methods are susceptible to noise disturbance, and can lead to instability of results. Besides, the edges of small-sized geologic bodies are difficult to be detected because of superimposed anomalies. In this paper, we give the definition of auto-ratios and present a new method for edge detection by using optimal auto-ratios of vertical derivatives, and elaborate mathematical implication and physical meaning of this method. The model test shows that the method using optimal auto-ratios of vertical gradients can greatly suppress noise disturbance and accurately detect the edges of geologic bodies which cannot be recognized by traditional edge detection methods. In application, we choose gravity data of the Yalujiang Basin where geological conditions are very complex to test the optimal auto-ratio method. The results show that the tectonic boundaries recognized by the optimal auto-ratios of the third-order vertical derivatives correspond well to distribution characteristics of real geologic bodies, which are in agreement with previous work. And the negative anomaly zones delineated by the auto-ratios reflect the work area of the Hunjiang coalfield rather well.

关键词： gradient algorithm Edge detection Noise disturbance Vertical gradient Optimal auto-ratio

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Optimization of ACE mode transition control schedule considering geometric adjustment speed

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INTERNATIONAL JOURNAL OF TURBO & JET-ENGINES 2022年第0期

作者： Song, Keran Jia, Linyuan Chen, Yuchun Tan, Tian Fan, Peiyang Northwestern Polytech Univ Sch Power & Energy Xian 710072 Peoples R China

Aiming to optimize the mode transition control schedule of the adaptive cycle engine (ACE), an optimization method based on a gradient algorithm was proposed. During the mode transition, the compressor surge margin, the total turbine inlet temperature and the combustion chamber fuel-air ratio are not exceeded. The integration of thrust by time was selected as the optimization objective. The geometric parameters were updated via the optimization target derivative. The speed limit of the geometric adjustment mechanism was also considered in the optimization process. The control schedules of two mode transition processes, from triple to double bypass mode and from double to triple-bypass mode were optimized. The optimization method presented in this paper can be applied to various mode transitions and the geometric adjustment speed meets all the constraints.

关键词： ACE geometric adjustment schedule gradient algorithm mode transition

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Measuring the distance from saddle points and driving to locate them over quantum control landscapes

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JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL 2015年第46期48卷

作者： Sun, Qiuyang Riviello, Gregory Wu, Re-Bing Rabitz, Herschel Princeton Univ Dept Chem Princeton NJ 08544 USA Tsinghua Univ Dept Automat Beijing 100084 Peoples R China TNList Ctr Quantum Informat Sci & Technol Beijing 100084 Peoples R China

Optimal control of quantum phenomena involves the introduction of a cost functional J to characterize the degree of achieving a physical objective by a chosen shaped electromagnetic field. The cost functional dependence upon the control forms a control landscape. Two theoretically important canonical cases are the landscapes associated with seeking to achieve either a physical observable or a unitary transformation. Upon satisfaction of particular assumptions, both landscapes are analytically known to be trap-free, yet possess saddle points at precise suboptimal J values. The presence of saddles on the landscapes can influence the effort needed to find an optimal field. As a foundation to future algorithm development and analyzes, we define metrics that identify the 'distance' from a given saddle based on the sufficient and necessary conditions for the existence of the saddles. algorithms are introduced utilizing the metrics to find a control such that the dynamics arrive at a targeted saddle. The saddle distance metric and saddle-seeking methodology is tested numerically in several model systems.

关键词： quantum optimal control control landscape saddle point gradient algorithm

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Sparse Analyzer Tool for Biomedical Signals

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SENSORS 2020年第9期20卷 2602-2602页

作者： Vujovic, Stefan Draganic, Andjela Zaric, Maja Lakicevic Orovic, Irena Dakovic, Milos Beko, Marko Stankovic, Srdjan Univ Montenegro Fac Elect Engn Podgorica 81000 Montenegro Univ Lusofona Humanidades & Tecnol COPELABS P-1700097 Lisbon Portugal Univ Nova Lisboa Fac Ciencias & Tecnol P-2829517 Monte De Caparica Portugal

The virtual (software) instrument with a statistical analyzer for testing algorithms for biomedical signals' recovery in compressive sensing (CS) scenario is presented. Various CS reconstruction algorithms are implemented with the aim to be applicable for different types of biomedical signals and different applications with under-sampled data. Incomplete sampling/sensing can be considered as a sort of signal damage, where missing data can occur as a result of noise or the incomplete signal acquisition procedure. Many approaches for recovering the missing signal parts have been developed, depending on the signal nature. Here, several approaches and their applications are presented for medical signals and images. The possibility to analyze results using different statistical parameters is provided, with the aim to choose the most suitable approach for a specific application. The instrument provides manifold possibilities such as fitting different parameters for the considered signal and testing the efficiency under different percentages of missing data. The reconstruction accuracy is measured by the mean square error (MSE) between original and reconstructed signal. Computational time is important from the aspect of power requirements, thus enabling the selection of a suitable algorithm. The instrument contains its own signal database, but there is also the possibility to load any external data for analysis.

关键词： biomedical signals compressive sensing concentration measure gradient algorithm OMP SIRA statistical analyzer sparse signal processing TV minimization virtual instrument

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Parameters identification of continuous system based on hybrid genetic algorithm

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26th Chinese Control Conference

作者： Hou Zhixiang Changsha Univ Sci & Technol Changsha 410076 Peoples R China

ISBN: (纸本)9787811240559

A new hybrid genetic algorithm is provided by adding up the advantages of the genetic algorithm and gradient algorithm, as uses the results of gradient algorithm improving the populations of genetic algorithm, and selects the best point as the start point of gradient algorithm next time by comparing the best point of genetic algorithm with the last results of gradient algorithm. Applying the method to estimating the parameters of continuous system the simulation results show it is more quickly than genetic algorithm and owes better anti-noise ability, and improves the defects of genetic algorithm with slower searching ability near a point and it provides a new method for the parameters estimation of continuous system.

关键词： system identification genetic algorithm gradient algorithm parameters estimation optimization

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An adaptive control allocation method based reconfigurable control system for Unmanned Aerial Vehicle 33

An adaptive control allocation method based reconfigurable c...

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33rd Chinese Control Conference (CCC)

作者： Wang Daobo Tang Xiaojun Wang Yin Nanjing Univ Aeronaut & Astronaut Coll Automat Nanjing 210016 Jiangsu Peoples R China Nanjing Univ Aeronaut & Astronaut Coll Astronaut Nanjing 210016 Jiangsu Peoples R China

ISBN: (纸本)9789881563842

This paper presents an adaptive control allocation scheme for the development of a reconfigurable control system, which allows for the redistribution of the control commands to the remaining actuators in the detection of actuator failures. The reconfigurable control task is considered as a constrained adaptive control allocation problem, and solved by using gradient algorithms. Simulation results have demonstrated the efficiency of the proposed technique in the presence of different failures of the actuator.

关键词： Unmanned Aerial Vehicle Reconfigurable Control Control Allocation gradient algorithm

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Vehicle image edge detection using image fusion at pixel level

Vehicle image edge detection using image fusion at pixel lev...

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IEEE International Conference on Automation and Logistics

作者： Xinnan Fan Lizhong Xu Xuewu Zhang Hanjing Hu Computer and Information Institute Hohai University HHU Changzhou China

ISBN: (纸本)9781424430567

After analyzing gradient algorithms, such as sobel operator, robert operator, prewitt operator and canny operator, an improved method of edge detection of vehicle image is proposed in the study, based on image fusion at pixel level. The experimental results show that this method can obtain integrated and consecutive vehicle edge’s image and make for the recognition of vehicle type.

关键词： Image Fusion gradient algorithm Vehicle Recognition Edge Detection image fusion Edge detection model cars vehicle pixel Imagery (Psychotherapy) images Integrate Sobel operator Recognition (Psychology) Canny edge detector

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A study of sub-pixel interpolation algorithm in digital speckle correlation method

A study of sub-pixel interpolation algorithm in digital spec...

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2008 International Conference on Optical Instruments and Technology

作者： LV Yong~(*a,b),FENG Qibo~a,QI Liangyu~b a School of Science,Beijing Jiaotong University,Beijing 100044,China b Dept,of Optical Information Science & Technology,Beijing Information Science & Technology University,Beijing 100192,China

Sub-pixel interpolation technique is a way that getting sub-pixel gray value by interpolation algorithm and then it is substituted into the correlation expression to calculate the sub-pixel *** is a key way to improve the displacement measurement accuracy in Digital Speckle Correlation Method(DSCM),meanwhile,it is more time consuming than other steps.A new quarter sub-pixel registration method is proposed which can significantly cut down the sub-pixel searching *** the premise of not reducing accuracy,an improved Taylor's series expansion in gradient algorithm is used to get higher registration *** the same time,a new cubic convolution interpolation method is proposed to get extremely high *** conclusions are proved by the results of the experimental system.

关键词： Displacement measurement Digital speckle correlation method(DSCM) Sub-pixel registration Interpolation algorithm Cubic convolution algorithm gradient algorithm

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