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variable-step integration method for milling chatter stability prediction with multiple delays

Science China(Technological Sciences) 2011年第12期54卷 3137-3154页

作者： ZHANG XiaoJian XIONG CaiHua DING Ye XIONG YouLun State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology Wuhan 430074 China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240 China

This paper analyzes the stability of milling with variable pitch cutter and tool runout cases characterized by multiple delays,and proposes a new variable-step numerical integration method for efficient and accurate stability prediction. The variable-step technique is emphasized here to expand the numerical integration method,especially for the low radial immersion cases with multiple delays. First,the calculation accuracy of the numerical integration method is discussed and the variable-step algorithm is developed for milling stability prediction for single-delay and multiple-delay cases,respectively. The milling stability with variable pitch cutter is analyzed and the result is compared with those predicted with the frequency domain method and the improved full-discretization method. The influence of the runout effect on the stability boundary is investigated by the presented method. The numerical simulation shows that the cutter runout effect increases the stability boundary,and the increasing stability limit is verified by the milling chatter experimental results in the previous research. The numerical and experiment results verify the validity of the proposed method.

关键词： variable-step numerical integration method milling chatter stability prediction multiple delays variable pitch cutter cutter runout

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A CLASS OF variable-step EXPLICIT NORDSIECK MULTIVALUE METHODS

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SIAM JOURNAL ON NUMERICAL ANALYSIS 1994年第5期31卷 1434-1451页

作者： BURRAGE, K SHARP, PW UNIV AUCKLAND DEPT MATHAUCKLANDNEW ZEALAND

Existing integrators for nonstiff initial value problems often use Adams, explicit Runge-Kutta, or extrapolation methods. Few integrators based on explicit multivalue methods have been developed, even though their generality can potentially lead to improved performance. Exploratory results are presented for a class of variable-step, three-step, three-stage, explicit Nordsieck multivalue methods of order six. The methods use the order six formula to advance approximations to the solution and scaled first derivatives from the previous three steps. An embedded order five formula is used to form the local error estimate. The methods have stage order five, which enables us to construct a local continuous extension of order five without performing extra derivative evaluations. The numerical results show, despite the exploratory nature of the work, that the new methods are competitive with (5,6) explicit Runge-Kutta pairs.

关键词： INITIAL VALUE MULTIVALUE METHOD MULTIstep NORDSIECK variable-step

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A variable-step RRT<sup>&x002A;</sup>Path Planning Algorithm for Quadrotors in Below-Canopy

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IEEE ACCESS 2020年 8卷 62980-62989页

作者： Liu, Ben Feng, Wenzhao Li, Tingting Hu, Chunhe Zhang, Junguo Beijing Forestry Univ Sch Technol Beijing 100083 Peoples R China Beijing Forestry Univ Key Lab State Forestry Adm Forestry Equipment & A Beijing 100083 Peoples R China

Rapidly-exploring random tree (RRT & x002A;) algorithm has been widely applied to path planning problem for quadrotor, which takes a great amount of static and dynamic constraints into account. However, conventional RRT & x002A;algorithm is suffering low convergence rate and efficiency in below-canopy environment, where is usually occupied with narrow aisles and uneven distributed obstacles. In order to enrich the forest information database and obtain information efficiently in blow-canopy, an improved variable-step RRT & x002A;algorithm has been proposed in this paper. In the proposed algorithm, the sampling nodes are determined by the target bias sampling strategy with variable probability. To further increase the efficiency of node generation and balance the searching time and security in areas with different obstacles densities, the event-triggered step size extension has been proposed according to hyperbolic tangent function. After that, both Euclidean distance and angle constraints are adopted in the cost function of node connection optimization. Then, the path is further optimized by path trimming and Bezier curves smooth method. Finally, the demonstration of the proposed algorithm is presented to show its efficiency, and the comparison result with existing RRT-like algorithms indicates that the performance of our algorithm is better than RRT, RRT & x002A;and DDRRT in terms of convergence and accuracy. Comparing to other classical path planning methods such as A(& x002A;), Artificial potential field and Fuzzy-logic, our method also shows its superiority.

关键词： RRT* Path planning quadrotor below-canopy environment variable-step

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Security control based on variable-step predictive approach for networked control system with denial-of-service attacks

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INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL 2023年第14期33卷 8475-8489页

作者： Li, Hongchao Gao, Hongjie Zuo, Zhiqiang Liu, Jiao Hebei Univ Technol Sch Artificial Intelligence Tianjin Peoples R China Tianjin Univ Sch Elect & Informat Engn Tianjin Peoples R China Hebei Univ Technol Sch Artificial Intelligence Tianjin 300130 Peoples R China

This paper investigates the variable-step predictive control problem for networked control system (NCS) with denial-of-service (DoS) attacks and model uncertainty. An event-based variable-step predictive scheme determined by accumulated error is firstly formulated to compensate the impact of DoS attacks. Based on the presence of DoS attacks and predictive control signals, NCS with DoS attacks is divided into three different operation modes and is described by switching system. With the above prediction scheme and system model, sufficient conditions are derived for ensuring the stability of the underlying system. Finally, an example is given to verify the validity of the theoretical results.

关键词： DoS attacks model uncertainty predictive control switching method variable-step

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A Novel Predictive Control for Active Power Filter using a variable-step LMS Algorithm 27

A Novel Predictive Control for Active Power Filter using a V...

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第27届中国控制与决策会议

作者： Li Yunlu Wang Dazhi Han Wei Liu Zhen Institute of Power System and Motor Drives College of Information&EngineeringNortheastern University College of Physics and Electronics Information Inner Mongolia University for Nationalities

ISBN: (纸本)9781479970179

In order to eliminate the impact of time delay to active power filter(APF),a novel predictive control based on variable-step LMS is proposed in this *** into account the power weights of errors and influence of previous state,the step size varies with both forgetting factor and follow-up *** factor can change the step size according to tracing error and follow-up factor can enhance the capacity of resisting *** introducing the proposed LMS with variable-step,the performance of the novel predictive control is improved both under steady and dynamic *** simulation between the proposed method and traditional LMS based predictive method is carried out and the results demonstrate the effectiveness of the proposed method.

关键词： variable-step LMS Predictive Control Active Power Filter

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An anti-interference variable-step adaptive algorithm and its application in active vibration control

An anti-interference variable-step adaptive algorithm and it...

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IEEE/OES China Ocean Acoustics (COA)

作者： Wang Chunyu He Lin Li Yan Zhang Xiaoping Zuo Lei Naval Univ Engn Inst Noise & Vibrat Natl Key Lab Ship Vibrat & Noise Wuhan Peoples R China Naval Univ Engn Ocean Elect Environm Inst Wuhan Peoples R China

ISBN: (纸本)9781467399784

Noise is unavoidable in a vibration control system due to the complexity of the actual application environment and the measuring limitation of sensing devices. In this paper, the jamming effects on the convergence process is analyzed and then we propose a new variable-step adaptive FxLMS algorithm which can reduce the negative effects of interference. The new algorithm can not only solve the problem in active vibration control (AVC) properly, but also decrease the misadjustment without slowing down the convergence rate. Simulation and experimental results show that the improved algorithm can effectively reduce the noise interference, and improve the application level of FxLMS algorithms in the case of vibration control.

关键词： anti-interference variable-step FxLMS algorithm active vibration control actual application

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Estimation for Power Quality Frequency Based on A variable-step ANF Algorithm

Estimation for Power Quality Frequency Based on A Variable-s...

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10th IEEE Conference on Industrial Electronics and Applications

作者： Su Junsen Gao Jie Zheng Changbao Hu Cungang Anhui Univ Sch Elect Engn & Automat Hefei 230039 Peoples R China Anhui Univ Natl Engn Lab Energy Saving Motor & Control Techn Hefei 230039 Peoples R China

ISBN: (纸本)9781479983896

In this paper, a variable-step ANF for estimation of power quality frequency is presented. This algorithm is fast and accurate. It still get a satisfied result under a high sampling rate. The algorithm of adaptive IIR notch filter with variable-step is presented in detail, and some variable-step method is presented. At last, the simulation is performed by Matlab and the result is compared under different SNR.

关键词： Frequency Estimation variable-step ANF

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A variable-step PHOTOVOLTAIC MPPT ALGORITHM BASED ON ADAPTIVE NEURO-FUZZY INFERENCE

A VARIABLE-STEP PHOTOVOLTAIC MPPT ALGORITHM BASED ON ADAPTIV...

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The 2011 International Conference on Mechanical Engineering and Technology

作者： Xu Fang Liu Jie Zhang Libin Wu Lebin Key Laboratory of Special Purpose Equipment and Advanced Processing Technology of Ministry of Education Zhejiang University of Technology

Due to the nonlinearity of the voltage-current characteristic in photovoltaic(PV) systems, maximum power point tracking(MPPT) techniques are employed to maximize the PV cells output power which depends on solar irradiance and temperature. The fixed-step perturbation and observation(P&O) MPPT algorithm is widely used as its easy implementation, but it is difficult to handle both dynamic response and steady-state precision. In this paper, a novel variable step size P&O algorithm based on adaptive neuro-fuzzy inference is proposed, the step size is automatically tuned according to the operating point to track the maximum power point. The theoretical analysis and the design principle of the proposed algorithm are provided and its feasibility is also verified by simulation and experiment results. Compared with the conventional fixed step P&O algorithm, the proposed approach can greatly improve the MPPT response speed and accuracy at steady state simultaneously.

关键词： Photovoltaic System Maximum power point tracking Adaptive Neuro-Fuzzy Inference System variable-step Perturbation and Observation method

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A variable step Size Adaptive Filtering Algorithm with Feedback Mechanism 2019

A Variable Step Size Adaptive Filtering Algorithm with Feedb...

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2nd International Conference on Electronics, Communications and Control Engineering (ICECC)

作者： Huang Youran Zhou Yunyao Wuhan Univ Technol Sch Informat & Engn Key Lab Fiber Opt Sensing Technol & Informat Proc Minist Educ Wuhan Hubei Peoples R China

ISBN: (纸本)9781450362634

Aiming at the problem that the traditional fixed-step LMS (Least Mean Square) algorithm can not satisfy both faster convergence speed and smaller steady-state error, an improved variable-step LMS algorithm is proposed in this paper. In this paper, an improved variable step size LMS algorithm based on Sigimoid function is *** this paper, the error signal of the previous time is introduced as a reference to control the shape and scope of the step factor curve. Compared with the error value of the current time, the feedback mechanism can make the system more stable. The simulation results show that, compared with other adaptive filtering algorithms proposed in recent years, the algorithm achieves steady state after 200 iterations on average, converges faster and runs faster by 7.2%. When the system mutates, it can quickly restore steady state again.

关键词： Adaptive filtering variable-step Sigmoid function

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A variable step Size Adaptive Filtering Algorithm with Feedback Mechanism

A Variable Step Size Adaptive Filtering Algorithm with Feedb...

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2019第二届电子，通讯与控制工程国际会议

作者： Huang Youran Zhou Yunyao Key Laboratory of Fiber Optic Sensing Technology and Information Processing Ministry of Education School of Information and Engineering Wuhan University of Technology

Aiming at the problem that the traditional fixed-step LMS（Least Mean Square） algorithm can not satisfy both faster convergence speed and smaller steady-state error, an improved variable-step LMS algorithm is proposed in this paper. In this paper, an improved variable step size LMS algorithm based on Sigimoid function is *** this paper, the error signal of the previous time is introduced as a reference to control the shape and scope of the step factor curve. Compared with the error value of the current time, the feedback mechanism can make the system more stable. The simulation results show that, compared with other adaptive filtering algorithms proposed in recent years, the algorithm achieves steady state after 200 iterations on average, converges faster and runs faster by 7.2%. When the system mutates, it can quickly restore steady state again.

关键词： Adaptive filtering variable-step Sigmoid function

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