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A Double-Interactively Recurrent Fuzzy Cerebellar Model Articulation Controller Model Combined with an Improved Particle Swarm Optimization Method for Fall Detection
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作者 Jyun-Guo Wang 《Computer Systems Science & Engineering》 2024年第5期1149-1170,共22页
In many Eastern and Western countries,falling birth rates have led to the gradual aging of society.Older adults are often left alone at home or live in a long-term care center,which results in them being susceptible t... In many Eastern and Western countries,falling birth rates have led to the gradual aging of society.Older adults are often left alone at home or live in a long-term care center,which results in them being susceptible to unsafe events(such as falls)that can have disastrous consequences.However,automatically detecting falls fromvideo data is challenging,and automatic fall detection methods usually require large volumes of training data,which can be difficult to acquire.To address this problem,video kinematic data can be used as training data,thereby avoiding the requirement of creating a large fall data set.This study integrated an improved particle swarm optimization method into a double interactively recurrent fuzzy cerebellar model articulation controller model to develop a costeffective and accurate fall detection system.First,it obtained an optical flow(OF)trajectory diagram from image sequences by using the OF method,and it solved problems related to focal length and object offset by employing the discrete Fourier transform(DFT)algorithm.Second,this study developed the D-IRFCMAC model,which combines spatial and temporal(recurrent)information.Third,it designed an IPSO(Improved Particle Swarm Optimization)algorithm that effectively strengthens the exploratory capabilities of the proposed D-IRFCMAC(Double-Interactively Recurrent Fuzzy Cerebellar Model Articulation Controller)model in the global search space.The proposed approach outperforms existing state-of-the-art methods in terms of action recognition accuracy on the UR-Fall,UP-Fall,and PRECIS HAR data sets.The UCF11 dataset had an average accuracy of 93.13%,whereas the UCF101 dataset had an average accuracy of 92.19%.The UR-Fall dataset had an accuracy of 100%,the UP-Fall dataset had an accuracy of 99.25%,and the PRECIS HAR dataset had an accuracy of 99.07%. 展开更多
关键词 Double interactively recurrent fuzzy cerebellar model articulation controller(D-IRFCMAC) improved particle swarm optimization(IPSO) fall detection
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Improved Clamped Diode Based Z-Source Network for Three Phase Induction Motor
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作者 D.Bensiker Raja Singh R.Suja Mani Malar 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期683-702,共20页
The 3Φinduction motor is a broadly used electric machine in industrial applications,which plays a vital role in industries because of having plenty of beneficial impacts like low cost and easiness but the problems lik... The 3Φinduction motor is a broadly used electric machine in industrial applications,which plays a vital role in industries because of having plenty of beneficial impacts like low cost and easiness but the problems like decrease in motor speed due to load,high consumption of current and high ripple occurrence of ripples have reduced its preferences.The ultimate objective of this study is to control change in motor speed due to load variations.An improved Trans Z Source Inverter(ΓZSI)with a clamping diode is employed to maintain constant input voltage,reduce ripples and voltage overshoot.To operate induction motor at rated speed,different controllers are used.The conventional Proportional-Inte-gral(PI)controller suffers from high settling time and maximum peak overshoot.To overcome these limitations,Fractional Order Proportional Integral Derivative(FOPID)controller optimized by Gray Wolf Optimization(GWO)technique is employed to provide better performance by eliminating maximum peak overshoot pro-blems.The proposed speed controller provides good dynamic response and controls the induction motor more effectively.The complete setup is implemented in MATLAB Simulation to verify the simulation results.The proposed approach provides optimal performance with high torque and speed along with less steady state error. 展开更多
关键词 Three phase induction motor voltage source inverter improvedΓZSI with clamping diode PI controller fractional order PID controller gray wolf optimizer
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Detection of Citrus Psyllid Based on Improved YOLOX Model
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作者 Haiman WANG Ting YU +2 位作者 Ganjun YI Deqiu LIN Min LUO 《Plant Diseases and Pests》 CAS 2023年第1期17-21,共5页
[Objectives]The paper was to explore a faster and more accurate detection method for citrus psyllid to prevent and control yellow-shoot disease and inhibit its transmission.[Methods]We used an improved YOLOX based edg... [Objectives]The paper was to explore a faster and more accurate detection method for citrus psyllid to prevent and control yellow-shoot disease and inhibit its transmission.[Methods]We used an improved YOLOX based edge detection method for psyllid,added Convolutional Block Attention Module(CBAM)to the backbone network,and further extracted important features in the channel and space dimensions.The Cross Entropy Loss in the object loss was changed to Focal Loss to further reduce the missed detection rate.[Results]The algorithm described in the study fitted in with the detection platform of psyllid.The data set of psyllid was taken in Lianjiang Orange Garden,Zhanjiang City,Guangdong Province,deeply adapted to the actual needs of agricultural and rural development.Based on YOLOX model,the backbone network and loss function were improved to achieve a more excellent detection method of citrus psyllid.The AP value of 85.66%was obtained on the data set of citrus psyllid,which was 2.70%higher than that of the original model,and the detection accuracies were 8.61%,4.32%and 3.62%higher than that of YOLOv3,YOLOv4-Tiny and YOLOv5-s,respectively,which had been greatly improved.[Conclusions]The improved YOLOX model can better identify citrus psyllid,and the accuracy rate has been improved,laying a foundation for the subsequent real-time detection platform. 展开更多
关键词 CITRUS improved YOLOX model Prevention and control of psyllid Artificial intelligence Object detection
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Improved Interleaved Single-Ended Primary Inductor-Converter forSingle-Phase Grid-Connected System
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作者 T.J.Thomas Thangam K.Muthu Vel 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期3459-3478,共20页
The generation of electricity based on renewable energy sources,parti-cularly Photovoltaic(PV)system has been greatly increased and it is simply insti-gated for both domestic and commercial uses.The power generated fr... The generation of electricity based on renewable energy sources,parti-cularly Photovoltaic(PV)system has been greatly increased and it is simply insti-gated for both domestic and commercial uses.The power generated from the PV system is erratic and hence there is a need for an efficient converter to perform the extraction of maximum power.An improved interleaved Single-ended Primary Inductor-Converter(SEPIC)converter is employed in proposed work to extricate most of power from renewable source.This proposed converter minimizes ripples,reduces electromagnetic interference due tofilter elements and the contin-uous input current improves the power output of PV panel.A Crow Search Algo-rithm(CSA)based Proportional Integral(PI)controller is utilized for controlling the converter switches effectively by optimizing the parameters of PI controller.The optimized PI controller reduces ripples present in Direct Current(DC)vol-tage,maintains constant voltage at proposed converter output and reduces over-shoots with minimum settling and rise time.This voltage is given to single phase grid via 1�Voltage Source Inverter(VSI).The command pulses of 1�VSI are produced by simple PI controller.The response of the proposed converter is thus improved with less input current.After implementing CSA based PI the efficiency of proposed converter obtained is 96%and the Total Harmonic Distor-tion(THD)is found to be 2:4%.The dynamics and closed loop operation is designed and modeled using MATLAB Simulink tool and its behavior is performed. 展开更多
关键词 improved interleaved DC-DC SEPIC converter crow search algorithm PI controller voltage source inverter PV array single phase grid
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Improved Rotor Flux Observer for Sensorless Control of PMSM with Adaptive Harmonic Elimination and Phase Compensation 被引量:3
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作者 Wei Xu Lei Wang +1 位作者 Yi Liu Frede Blaabjerg 《CES Transactions on Electrical Machines and Systems》 CSCD 2019年第2期151-159,共9页
In this paper,a sensorless control strategy of a permanent magnet synchronous machine(PMSM)based on an improved rotor flux observer(IFO)is proposed.Due to the unknown integral initial value and the high harmonics caus... In this paper,a sensorless control strategy of a permanent magnet synchronous machine(PMSM)based on an improved rotor flux observer(IFO)is proposed.Due to the unknown integral initial value and the high harmonics caused by current sampling and inverter nonlinearities,the flux linkage estimated by traditional rotor flux observer may be inaccurate.In order to address these issues,a self-adaptive band-pass filter(SABPF)is designed to eliminate the DC component and high-frequency harmonics of the estimated equivalent rotor flux linkage.Furthermore,in order to avoid that the design of PI parameter is influenced by the amplitude of equivalent rotor flux linkage,an improved phase-locked loop(IPLL)is employed to obtain the rotor speed and to normalize the estimated equivalent rotor flux linkage.In addition,angle shift caused by an SABPF is compensated to improve the accuracy of the estimated flux linkage angle.Besides,the parameter robustness of this method is analyzed in detail.Finally,simulation and experimental results demonstrate the effectiveness and parameter robustness of the proposed method. 展开更多
关键词 improved phase-locked loop(IPLL) sensorless control improved flux observer(IFO) self-adaptive band-pass filter(SABPF).
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Improved Bat Algorithm Based Energy Efficient Congestion Control Scheme for Wireless Sensor Networks 被引量:1
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作者 Mukhdeep Singh Manshahia Mayank Dave Satya Bir Singh 《Wireless Sensor Network》 2016年第11期229-241,共14页
Energy conservation and congestion control are widely researched topics in Wireless Sensor Networks in recent years. The main objective is to develop a model to find the optimized path on the basis of distance between... Energy conservation and congestion control are widely researched topics in Wireless Sensor Networks in recent years. The main objective is to develop a model to find the optimized path on the basis of distance between source and destination and the residual energy of the node. This paper shows an implementation of nature inspired improved Bat Algorithm to control congestion in Wireless Sensor Networks at transport layer. The Algorithm has been applied on the fitness function to obtain an optimum solution. Simulation results have shown improvement in parameters like network lifetime and throughput as compared with CODA (Congestion Detection and Avoidance), PSO (Particle Swarm Optimization) algorithm and ACO (Ant Colony Optimization). 展开更多
关键词 improved Bat Algorithm Congestion control Wireless Sensor Networks
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Two-Stage Planning of Distributed Power Supply and Energy Storage Capacity Considering Hierarchical Partition Control of Distribution Network with Source-Load-Storage
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作者 Junhui Li Yuqing Zhang +4 位作者 Can Chen Xiaoxiao Wang Yinchi Shao Xingxu Zhu Cuiping Li 《Energy Engineering》 EI 2024年第9期2389-2408,共20页
Aiming at the consumption problems caused by the high proportion of renewable energy being connected to the distribution network,it also aims to improve the power supply reliability of the power system and reduce the ... Aiming at the consumption problems caused by the high proportion of renewable energy being connected to the distribution network,it also aims to improve the power supply reliability of the power system and reduce the operating costs of the power system.This paper proposes a two-stage planning method for distributed generation and energy storage systems that considers the hierarchical partitioning of source-storage-load.Firstly,an electrical distance structural index that comprehensively considers active power output and reactive power output is proposed to divide the distributed generation voltage regulation domain and determine the access location and number of distributed power sources.Secondly,a two-stage planning is carried out based on the zoning results.In the phase 1 distribution network-zoning optimization layer,the network loss is minimized so that the node voltage in the area does not exceed the limit,and the distributed generation configuration results are initially determined;in phase 2,the partition-node optimization layer is planned with the goal of economic optimization,and the distance-based improved ant lion algorithm is used to solve the problem to obtain the optimal distributed generation and energy storage systemconfiguration.Finally,the IEEE33 node systemwas used for simulation.The results showed that the voltage quality was significantly improved after optimization,and the overall revenue increased by about 20.6%,verifying the effectiveness of the two-stage planning. 展开更多
关键词 Zoning control two-stage planning site selection and capacity determination optimized scheduling improved ant lion algorithm
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Study of improved gray predictive PID control algorithm 被引量:1
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作者 XIE Shou-yong LI Xi-wen +1 位作者 YANG Shu-zi YANG Ming-jin 《重庆邮电大学学报(自然科学版)》 北大核心 2009年第2期189-191,共3页
According to these characteristics of the movement of the special platform servo,a new improved grey predictive PID control algorithm was proposed based on the grey predictive PID,and then the algorithm was simulated ... According to these characteristics of the movement of the special platform servo,a new improved grey predictive PID control algorithm was proposed based on the grey predictive PID,and then the algorithm was simulated by MATLAB.As a result that it can improve the response speed and stability of the system,and meet the demand of the system. 展开更多
关键词 PID控制算法 灰色预测 MATLAB 算法模拟 反应速度 系统 伺服
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Improved Bacterial Foraging Optimization Algorithm Based on Fuzzy Control Rule Base
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作者 Cui-Cui Du Xu-Gang Feng Jia-Yan Zhang 《Journal of Electronic Science and Technology》 CAS CSCD 2017年第3期283-288,共6页
Manual construction of a rule base for a fuzzy system is the hard and time-consuming task that requires expert knowledge.In this paper we proposed a method based on improved bacterial foraging optimization(IBFO),whi... Manual construction of a rule base for a fuzzy system is the hard and time-consuming task that requires expert knowledge.In this paper we proposed a method based on improved bacterial foraging optimization(IBFO),which simulates the foraging behavior of “E.coli” bacterium,to tune the Gaussian membership functions parameters of an improved Takagi-Sugeno-Kang fuzzy system(C-ITSKFS) rule base.To remove the defect of the low rate of convergence and prematurity,three modifications were produced to the standard bacterial foraging optimization(BFO).As for the low accuracy of finding out all optimal solutions with multi-method functions,the IBFO was performed.In order to demonstrate the performance of the proposed IBFO,multiple comparisons were made among the BFO,particle swarm optimization(PSO),and IBFO by MATLAB simulation.The simulation results show that the IBFO has a superior performance. 展开更多
关键词 Index Terms--Fuzzy control system Gaussian membership functions improved bacterial foraging optimization (IBFO) particle swarm optimization (PSO)
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A Control Strategy for Smoothing Active Power Fluctuation of Wind Farm with Flywheel Energy Storage System Based on Improved Wind Power Prediction Algorithm
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作者 J. C. Wang X. R. Wang 《Energy and Power Engineering》 2013年第4期387-392,共6页
The fluctuation of active power output of wind farm has many negative impacts on large-scale wind power integration into power grid. In this paper, flywheel energy storage system (FESS) was connected to AC side of the... The fluctuation of active power output of wind farm has many negative impacts on large-scale wind power integration into power grid. In this paper, flywheel energy storage system (FESS) was connected to AC side of the doubly-fed induction generator (DFIG) wind farm to realize smooth control of wind power output. Based on improved wind power prediction algorithm and wind speed-power curve modeling, a new smooth control strategy with the FESS was proposed. The requirement of power system dispatch for wind power prediction and flywheel rotor speed limit were taken into consideration during the process. While smoothing the wind power fluctuation, FESS can track short-term planned output of wind farm. It was demonstrated by quantitative analysis of simulation results that the proposed control strategy can smooth the active power fluctuation of wind farm effectively and thereby improve power quality of the power grid. 展开更多
关键词 WIND POWER Generation FESS WIND POWER Prediction improved Time-series Algorithm Active POWER Smooth control
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Application of Improved Fuzzy Controller in Networked Control System
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作者 ZHANG Qian GUO Xi-jin WANG Zhen TIAN Xi-lan 《Journal of China University of Mining and Technology》 EI 2006年第4期500-504,共5页
Aiming at the problem of network-induced delay and data dropout in networked control system, an improved fuzzy controller is proposed in this paper. Considering the great influence of a controller on the performance o... Aiming at the problem of network-induced delay and data dropout in networked control system, an improved fuzzy controller is proposed in this paper. Considering the great influence of a controller on the performance of control system, an improved controller with a second order fuzzy controller and network-induced delay compensator being added to the basic fuzzy controller is proposed to realize self-regulation on-line. For this type of controller, neither plant model nor measurement of network delay is required. So it is capable of automatically adjusting quantified factor, pro- portional factor, and integral factor according to the control system error and its derivative. The design makes full use of the advantages of quickness in operation and reduction of steady state error because of its integral function. The con- troller has a good control effect on time-delay and can keep a better performance by self-regulation on-line in the net- work with data dropout and interference. It is good in quickness, adaptability, and robustness, which is favorable for controlling the long time-delay system. 展开更多
关键词 networked control system improved fuzzy controller network-induced delay data dropout
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Speed Control of Motor Based on Improved Glowworm Swarm Optimization
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作者 Zhenzhou Wang Yan Zhang +2 位作者 Pingping Yu Ning Cao Heiner Dintera 《Computers, Materials & Continua》 SCIE EI 2021年第10期503-519,共17页
To better regulate the speed of brushless DC motors,an improved algorithm based on the original Glowworm Swarm Optimization is proposed.The proposed algorithm solves the problems of poor robustness,slow convergence,an... To better regulate the speed of brushless DC motors,an improved algorithm based on the original Glowworm Swarm Optimization is proposed.The proposed algorithm solves the problems of poor robustness,slow convergence,and low accuracy exhibited by traditional PID controllers.When selecting the glowworm neighborhood set,an optimization scheme based on the growth and competition behavior of weeds is applied to a single glowworm to prevent falling into a local optimal solution.After the glowworm’s position is updated,the league selection operator is introduced to search for the global optimal solution.Combining the local search ability of the invasive weed optimization with the global search ability of the league selection operator enhances the robustness of the algorithm and also accelerates the convergence speed of the algorithm.The mathematical model of the brushless DC motor is established,the PID parameters are tuned and optimized using improved Glowworm Swarm Optimization algorithm,and the speed of the brushless DC motor is adjusted.In a Simulink environment,a double closed-loop speed control model was established to simulate the speed control of a brushless DC motor,and this simulation was compared with a traditional PID control.The simulation results show that the model based on the improved Glowworm Swarm Optimization algorithm has good robustness and a steady-state response speed for motor speed control. 展开更多
关键词 PID speed control improved Glowworm Swarm Optimization brushless DC motor
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A Novel Tuning Method for Predictive Control of VAV Air Conditioning System Based on Machine Learning and Improved PSO
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作者 Ning He Kun Xi +1 位作者 Mengrui Zhang Shang Li 《Journal of Beijing Institute of Technology》 EI CAS 2022年第4期350-361,共12页
The variable air volume(VAV)air conditioning system is with strong coupling and large time delay,for which model predictive control(MPC)is normally used to pursue performance improvement.Aiming at the difficulty of th... The variable air volume(VAV)air conditioning system is with strong coupling and large time delay,for which model predictive control(MPC)is normally used to pursue performance improvement.Aiming at the difficulty of the parameter selection of VAV MPC controller which is difficult to make the system have a desired response,a novel tuning method based on machine learning and improved particle swarm optimization(PSO)is proposed.In this method,the relationship between MPC controller parameters and time domain performance indices is established via machine learning.Then the PSO is used to optimize MPC controller parameters to get better performance in terms of time domain indices.In addition,the PSO algorithm is further modified under the principle of population attenuation and event triggering to tune parameters of MPC and reduce the computation time of tuning method.Finally,the effectiveness of the proposed method is validated via a hardware-in-the-loop VAV system. 展开更多
关键词 model predictive control(MPC) parameter tuning machine learning improved particle swarm optimization(PSO)
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How Can Macroeconomic Control Be Improved?
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作者 陈佳贵 《China Economist》 2007年第3期10-13,共4页
Ⅰ.New macroeconomic controls not fully realised China introduced a new set of macroeconomic controls in 2004 in an attempt to control excessive growth.Due to the impact of the Asian Financial Crisis, China’s economy... Ⅰ.New macroeconomic controls not fully realised China introduced a new set of macroeconomic controls in 2004 in an attempt to control excessive growth.Due to the impact of the Asian Financial Crisis, China’s economy grew at a low growth rate between 1998 and 2001.However it accelerated from 2002 onwards,and saw a GDP increase of 11%in the fourth quarler of 2003,a historical high since 1997 展开更多
关键词 How Can Macroeconomic control Be improved THAN OVER
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Application of PDCA in improving hand hygiene compliance and nosocomial infection quality in orthopedics
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作者 Ya-Ping Su Rui-Ling Li +2 位作者 Yuan-Yuan Wang Yu-Rui Zhang Ya-Jie Ji 《Frontiers of Nursing》 2024年第3期327-336,共10页
Objective:To explore the effect of the Plan-Do-Check-Action(PDCA)cycle on hand hygiene and nosocomial infection quality of or thopedic medical staff.Methods:The whole year of 2021 was selected to monitor the quality o... Objective:To explore the effect of the Plan-Do-Check-Action(PDCA)cycle on hand hygiene and nosocomial infection quality of or thopedic medical staff.Methods:The whole year of 2021 was selected to monitor the quality of hand hygiene and hospitalization.Follow-up monitoring and real-time recording during the period of morning shift and medical operation concentration time,and compare the compliance of hand hygiene before and after implementation,and evaluate the quality of nosocomial infection.Results:The hand hygiene compliance of doctors and nurses in stage P was 82%.The compliance of medical staff in stage D was 93%.The compliance of stage C was 94%and that of stage A was 95%.The quality score of hospital self-examination nosocomial infection was also significantly increased.Conclusions:The PDCA management cycle can effectively improve the compliance of hand hygiene and the nosocomial infection quality,which is wor thy of circulatory application in or thopedic nosocomial infection quality control,especially improving the quality of hand hygiene. 展开更多
关键词 hand hygiene quality improvement PDCA nosocomial infection infection control nursing management
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Extremum seeking control for UAV close formation flight via improved pigeon-inspired optimization 被引量:2
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作者 YUAN GuangSong DUAN HaiBin 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2024年第2期435-448,共14页
This paper proposes a comprehensive design scheme for the extremum seeking control(ESC)of the unmanned aerial vehicle(UAV)close formation flight.The proposed design scheme combines a Newton-Raphson method with an exte... This paper proposes a comprehensive design scheme for the extremum seeking control(ESC)of the unmanned aerial vehicle(UAV)close formation flight.The proposed design scheme combines a Newton-Raphson method with an extended Kalman filter(EKF)to dynamically estimate the optimal position of the following UAV relative to the leading UAV.To reflect the wake vortex effects reliably,the drag coefficient induced by the wake vortex is considered as a performance function.Then,the performance function is parameterized by the first-order and second-order terms of its Taylor series expansion.Given the excellent performance of nonlinear estimation,the EKF is used to estimate the gradient and the Hessian matrix of the parameterized performance function.The output feedback of the proposed scheme is determined by iterative calculation of the Newton-Raphson method.Compared with the traditional ESC and the classic ESC,the proposed design scheme avoids the slow continuous time integration of the gradient.This allows a faster convergence of relative position extremum.Furthermore,the proposed method can provide a smoother command during the seeking process as the second-order term of the performance function is taken into account.The convergence analysis of the proposed design scheme is accomplished by showing that the output feedback is a supermartingale sequence.To improve estimation performance of the EKF,a improved pigeon-inspired optimization(IPIO)is proposed to automatically tune the noise covariance matrix.Monte Carlo simulations for a three-UAV close formation show that the proposed design scheme is robust to the initial position of the following UAV. 展开更多
关键词 unmanned aerial vehicle close formation extremum seeking control Newton-Raphson method improved pigeon-inspired optimization
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Improved sliding-mode control for tracking global maximum power of triple-series-parallel ladder photovoltaic arrays under uneven shadowing
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作者 Rama Koteswara Rao Alla Kandipati Rajani Ravindranath Tagore Yadlapalli 《Clean Energy》 EI CSCD 2024年第5期54-72,共19页
This paper presents an innovative way to enhance the performance of photovoltaic(PV)arrays under uneven shadowing conditions.The study focuses on a triple-series–parallel ladder configuration to exploit the benefits ... This paper presents an innovative way to enhance the performance of photovoltaic(PV)arrays under uneven shadowing conditions.The study focuses on a triple-series–parallel ladder configuration to exploit the benefits of increased power generation while ad-dressing the challenges associated with uneven shadowing.The proposed methodology focuses on the implementation of improved sliding-mode control technique for efficient global maximum power point tracking.Sliding-mode control is known for its robustness in the presence of uncertainties and disturbances,making it suitable for dynamic and complex systems such as PV arrays.This work employs a comprehensive simulation framework to comment on the performance of the suggested improved sliding-mode control strategy in uneven shadowing scenarios.Comparative analysis has been done to show the better effectiveness of the suggested method than the traditional control strategies.The results demonstrate a remarkable enhancement in the tracking accuracy of the global maximum power point,leading to enhanced energy-harvesting capabilities under challenging environmental conditions.Furthermore,the proposed approach exhibits robustness and adaptability in mitigating the effect of shading on the PV array,thereby increasing overall system efficiency.This research contributes valuable insights into the development of advanced control strategies for PV arrays,particularly in the context of triple-series–parallel ladder configurations operating under uneven shadowing conditions.Under short narrow shading conditions,the improved sliding-mode control method tracks the maximum power better compared with perturb&observe at 20.68%,incremental-conductance at 68.78%,fuzzy incremental-conductance at 19.8%,and constant-velocity sliding-mode control at 1.25%.The improved sliding-mode control method has 60%less chattering than constant-velocity sliding-mode control under shading conditions. 展开更多
关键词 improved sliding-mode control PV array global maximum power point SERIES-PARALLEL boost converter
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Direct Yaw Moment Control for Distributed Drive Electric Vehicle Handling Performance Improvement 被引量:30
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作者 YU Zhuoping LENG Bo +2 位作者 XIONG Lu FENG Yuan SHI Fenmiao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第3期486-497,共12页
For a distributed drive electric vehicle(DDEV) driven by four in-wheel motors, advanced vehicle dynamic control methods can be realized easily because motors can be controlled independently, quickly and precisely. A... For a distributed drive electric vehicle(DDEV) driven by four in-wheel motors, advanced vehicle dynamic control methods can be realized easily because motors can be controlled independently, quickly and precisely. And direct yaw-moment control(DYC) has been widely studied and applied to vehicle stability control. Good vehicle handling performance: quick yaw rate transient response, small overshoot, high steady yaw rate gain, etc, is required by drivers under normal conditions, which is less concerned, however. Based on the hierarchical control methodology, a novel control system using direct yaw moment control for improving handling performance of a distributed drive electric vehicle especially under normal driving conditions has been proposed. The upper-loop control system consists of two parts: a state feedback controller, which aims to realize the ideal transient response of yaw rate, with a vehicle sideslip angle observer; and a steering wheel angle feedforward controller designed to achieve a desired yaw rate steady gain. Under the restriction of the effect of poles and zeros in the closed-loop transfer function on the system response and the capacity of in-wheel motors, the integrated time and absolute error(ITAE) function is utilized as the cost function in the optimal control to calculate the ideal eigen frequency and damper coefficient of the system and obtain optimal feedback matrix and feedforward matrix. Simulations and experiments with a DDEV under multiple maneuvers are carried out and show the effectiveness of the proposed method: yaw rate rising time is reduced, steady yaw rate gain is increased, vehicle steering characteristic is close to neutral steer and drivers burdens are also reduced. The control system improves vehicle handling performance under normal conditions in both transient and steady response. State feedback control instead of model following control is introduced in the control system so that the sense of control intervention to drivers is relieved. 展开更多
关键词 direct yaw moment control distributed drive electric vehicle handling performance improvement state feedback control
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Improved LMI representations for delay-independent and delay-dependent stability conditions 被引量:1
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作者 YingminJIA HidekiKokame 《控制理论与应用(英文版)》 EI 2003年第1期70-76,共7页
Some new linear matrix inequality (LMI) representations for delay-independent and delay-dependent stability conditions are obtained by introducing additional matrices and eliminating the product coupling of the system... Some new linear matrix inequality (LMI) representations for delay-independent and delay-dependent stability conditions are obtained by introducing additional matrices and eliminating the product coupling of the system matrices and the Lya-punov matrices. The results improve conservativeness of the given conditions for the analysis and the design of tune-delay systems with polytopic-type uncertainty. 展开更多
关键词 improved LMIs Polytopic-type uncertainty Robust control Time-delay systems
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Efficiency Improvement of PEM Fuel Cells via Humidity Control 被引量:1
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作者 Ahmad Haddad Louay Elsoufi +1 位作者 Marc Mannah Hasan Bazzi 《Journal of Control Science and Engineering》 2016年第1期26-35,共10页
PEM (Proton Exchange Membrane) fuel cell is a promising renewable energy source to a wide range of applications for its clean products and high power density. However, controlling its humidity is a challenging probl... PEM (Proton Exchange Membrane) fuel cell is a promising renewable energy source to a wide range of applications for its clean products and high power density. However, controlling its humidity is a challenging problem due to the interdependence of several phenomena contributing in membrane's water content. This work deals with efficiency improvement of PEM fuel cells via humidity control. An innovative strategy of control based on the model of Ref. [1] is proposed. It consists on regulating gas humidification rates according to the power demand so that to minimize power losses. The proposed control takes into consideration constraints related to humidification in order to avoid dry out or flooding of the membrane. Simulations results show that time-phasing between hydrogen and oxygen humidification rates plays an important role in minimizing power losses. The proposed control shows significant improvement in the fuel cell's efficiency up to 20%. 展开更多
关键词 PEM fuel cell mathematical modeling humidity control efficiency improvement.
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