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Robust Sparsity-Aware RLS Algorithms With Jointly-Optimized parameters Against Impulsive Noise

IEEE SIGNAL PROCESSING LETTERS 2022年 29卷 1037-1041页

作者： Yu, Yi Lu, Lu Zakharov, Yuriy de Lamare, Rodrigo C. Chen, Badong Southwest Univ Sci & Technol Sch Informat Engn Robot Technol Used Special Environm Key Lab Sichu Mianyang 621010 Sichuan Peoples R China Sichuan Univ Sch Elect & Informat Engn Chengdu 610065 Peoples R China Univ York Dept Elect York YO10 5DD N Yorkshire England Pontificia Univ Catolica Rio de Janeiro CETUC BR-22451900 Rio de Janeiro Brazil Xi An Jiao Tong Univ Inst Artificial Intelligence & Robot Xian 710049 Shaanxi Peoples R China

This paper proposes a unified sparsity-aware robust recursive least-squares RLS (S-RRLS) algorithm for the identification of sparse systems under impulsive noise. The proposed algorithm generalizes multiple algorithms only by replacing the specified criterion of robustnessand sparsity-aware penalty. Furthermore, by jointly optimizing the forgetting factor and the sparsity penalty parameter, we develop the jointly-optimized S-RRLS (JO-S-RRLS) algorithm, which not only exhibits low misadjustment but also can track well sudden changes of a sparse system. Simulations in impulsive noise scenarios demonstrate that the proposed S-RRLS and JO-S-RRLS algorithms outperform existing techniques.

关键词： Signal processing algorithms Robustness Optimized production technology Gaussian noise Steady-state Kalman filters Underwater acoustics Impulsive noises variable parameters robust RLS sparse systems

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Ultrasonic assisted pecking drilling process for CFRP/Ti laminated materials

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JOURNAL OF MANUFACTURING PROCESSES 2023年 108卷 834-851页

作者： Liu, Fengyu Chen, Tao Duan, Zhenyan Suo, Yuhao Zhang, Chuandian Wuhan Univ Technol Sch Mech & Elect Engn Wuhan 430070 Peoples R China

Carbon fiber reinforced polymer (CFRP)/titanium alloy (Ti) laminated materials are widely used in aerospace and marine industries because of their excellent physical and electrochemical properties. The extensive demand requires a higher level of hole making technology to reduce the material damage caused by hole making. In this paper, we adopt a novel machining method, which combines Ultrasonic Assisted Drilling (UAD) and pecking drilling to generate a new machining method, Ultrasonic Pecking Drilling (UPD). Based on this, this study compares Conventional Drilling (CD), UAD and UPD in terms of thrust using orthogonal test method. In this paper, CFRP exiting delamination damage is investigated for three processing methods, and indirect measurement of interface temperature as well as detection of CFRP entrance delamination damage are carried out for UPD process. In addition, the tool wear and the exit burr of titanium alloy are analyzed for the three processes under different parameters. The test results show that UPD performed better in terms of thrust, the lowest thrust force is reduced by 35.1 % and 14.8 % at low feeds, respectively. CFRP exit delamination and tool wear are also good compared to both CD and UAD. Compared to CD, the maximum delamination damage decreased by 6.37 %. Besides, UPD results in better hole surface quality, where the roughness can be reduced by up to about 40 %. The obtained results show that UPD is a worthwhile option for drilling CFRP/Ti laminated materials.

关键词： CFRP/Ti laminates Ultrasonic assisted drilling Pecking drilling variable parameters

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Study on Cutting Force and Surface Topography of Peripheral Milling CFRP

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EXPERIMENTAL TECHNIQUES 2023年第3期47卷 633-653页

作者： Li, X. Jiao, A. Xu, M. Liu, G. Univ Sci & Technol Liaoning Coll Mech Engn & Automat Anshan 114051 Peoples R China HIT Anshan Inst Ind Technol Anshan 114001 Peoples R China

When constant parameters are used for peripheral milling CFRP, it is difficult to meet the requirement of high quality, so variable parameters machining is proposed. First, the response surface method was used to explore the effect of changing cutting conditions on the interaction of spindle speed, cutting depth and feed speed on radial force. The surface topography and roughness after the test were observed and analyzed. The results show that defects are more likely to occur at the entrance and the exit area than the central area. Taking the minimum radial force as the experimental goal, the optimal parameters combination was obtained and used for finite element and experimental verification. Second, the variable parameters milling were used the cemented carbide tool and PCD tool. The radial force, surface topography and roughness were analyzed and the optimized variable parameters combination was obtained. The results show that the high spindle speed, low feed speed and low cutting depth are beneficial to improve the surface quality at the entrance and the exit area when the machining parameters at the centra area remain unchanged. Meanwhile, when the parameters change abruptly, the fluctuation of the radial force at the variable parameters area is decreased. The variable parameters compared to constant parameters, the surface roughness of the machining with the cemented carbide tool at the entrance area by 29.7% and 7.4%, respectively and the machining with PCD tool at the exit and the entrance area decreased by 60.5%, 43.5% and 38.8%, 51.9%, respectively. Compared with the cemented carbide tool, the radial force of the PCD tool is more stable and the surface quality is further improved.

关键词： CFRP Peripheral milling Surface topography Finite element method variable parameters

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An application of data-driven modeling for hydroelasticity of an elastically supported semi-circular pipe conveying fluid

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ENGINEERING COMPUTATIONS 2023年第5期40卷 1195-1227页

作者： Xu, Jianhang Li, Peng Yang, Yiren Southwest Jiaotong Univ Sch Mech & Aerosp Engn Chengdu Peoples R China

PurposeThe paper aims to develop an efficient data-driven modeling approach for the hydroelastic analysis of a semi-circular pipe conveying fluid with elastic end supports. Besides the structural displacement-dependent unsteady fluid force, the steady one related to structural initial configuration and the variable structural parameters (i.e. the variable support stiffness) are considered in the ***/methodology/approachThe steady fluid force is treated as a pipe preload, and the elastically supported pipe-fluid model is dealt with as a prestressed hydroelastic system with variable parameters. To avoid repeated numerical simulations caused by parameter variation, structural and hydrodynamic reduced-order models (ROMs) instead of conventional computational structural dynamics (CSD) and computational fluid dynamics (CFD) solvers are utilized to produce data for the update of the structural, hydrodynamic and hydroelastic state-space equations. Radial basis function neural network (RBFNN), autoregressive with exogenous input (ARX) model as well as proper orthogonal decomposition (POD) algorithm are applied to modeling these two ROMs, and a hybrid framework is proposed to incorporate *** proposed approach is validated by comparing its predictions with theoretical solutions. When the steady fluid force is absent, the predictions agree well with the "inextensible theory". The pipe always loses its stability via out-of-plane divergence first, regardless of the support stiffness. However, when steady fluid force is considered, the pipe remains stable throughout as flow speed increases, consistent with the "extensible theory". These results not only verify the accuracy of the present modeling method but also indicate that the steady fluid force, rather than the extensibility of the pipe, is the leading factor for the differences between the in- and extensible ***/valueThe steady fluid force and the variable structural parameters are co

关键词： Data-driven modeling Reduced-order methods Semi-circular pipe conveying fluid Hydroelasticity Steady fluid force variable parameters

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MATRIX Motor with Individual Winding Current Control Capability for variable parameters and Iron Loss Suppression 21

MATRIX Motor with Individual Winding Current Control Capabil...

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International Conference on Electrical Machines (ICEM)

作者： Hijikata, H. Akatsu, K. Miyama, Y. Arita, H. Daikoku, A. Shibaura Inst Technol Dept Funct Control Syst Tokyo 108 Japan Shibaura Inst Technol Dept Elect Engn Tokyo 108 Japan Mitsubishi Electr Corp Adv Technol R&D Ctr Amagasaki Hyogo Japan

ISBN: (纸本)9781479943883

This paper describes a novel motor-drive system which includes the multi-phase open-end windings for an individual winding current control in order to realize the variable parameters. Each armature winding is connected with the insulated full-bridge inverter for the arbitrary excitation waveform. The proposed construction can extend the operating area and can distribute the high efficiency area. Furthermore, the proposed multi-phase drive can suppress the harmonic iron loss under the flux weakening operation because the individual control can regulate the instantaneous flux density in each stator tooth even though the motor consists of the full-pitch distributed winding. In this paper, the down size model was designed to confirm the principle. It was shown that the downsize model can expand the operating range, can distribute high efficiency area, and can suppress the iron loss by the controlled flux density in each stator tooth by some simulation and experimental results.

关键词： Harmonic iron loss Individual winding current control Interior permanent magnet synchronous motor Motor-drive integration Multi-phase motor variable parameters

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Study on variable Parameter Helical Milling of TC4 Titanium Alloy Tube

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INTERNATIONAL JOURNAL OF PRECISION ENGINEERING AND MANUFACTURING 2023年第11期24卷 1947-1959页

作者： Jiao, Anyuan Yuan, Jingqi Zhang, Yue Zhang, Jialong Miao, Yongxin Liu, Guojun Univ Sci & Technol Liaoning Sch Appl Technol Anshan 114041 Peoples R China Univ Sci & Technol Liaoning Sch Mech Engn & Automat Anshan 114041 Peoples R China

Titanium alloy was widely used in various tubing systems due to the excellent performance, and tubes were usually used as a connection channel for conveying media with holes. However, the stability and dependability of media transmission in the tubing system would be directly impacted by the quality of the holes. This study primarily focused on TC4 titanium alloy tubes to investigate variable parameter helical milling holes to enhance the quality of tube connection holes. The finite element method simulation and response surface method were used to examine the relationship between each process parameter and the accuracy of the holes. Thus, a better combination of process parameters was projected. And based on this, a variable parameter hole-making scheme was proposed to lower the burrs at the entrance and exit of holes and enhance the quality of the wall of holes. The results showed that the aperture of 5.015 mm after processing the titanium alloy tube using the better process parameters met the requirements of H8. Additionally, the burrs at the hole entrance were 1.4 & mu;m, the burrs at the hole exit were not noticeable, and the surface roughness Rz and Ra were 1.459 & mu;m and 0.232 & mu;m, respectively, met the requirements of process technology. The variable parameter helical milling technique used in this study could significantly raise the quality of holes produced in titanium alloy tubes and serve as a valuable benchmark for tubes of other materials.

关键词： TC4 titanium alloy Helical milling FEM RSM variable parameters

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Photocatalytic NO removal by WO3 samples prepared via a ball milling treatment under different parameters

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INORGANIC AND NANO-METAL CHEMISTRY 2024年第6期54卷 547-559页

作者： Wang, Yuqing Chang, Fei Wei, Zhixun Yang, Cheng Liu, Deng-guo Yan, Tianyi Pang, Qingyun Chen, Shengwen Univ Shanghai Sci & Technol Sch Mat & Chem Shanghai Peoples R China Univ Shanghai Sci & Technol Sch Environm & Architecture Shanghai Peoples R China Shanghai Environm Monitoring Ctr Shanghai Peoples R China Shanghai Polytech Univ Sch Environm & Mat Engn Shanghai Peoples R China

In this investigation, a series of WO3 samples were achieved by a ball milling treatment under variable synthetic parameters (milling time from 0.5 to 8 h, grinding speed from 100 to 500 rpm, and several solvents as dispersants). These samples were characterized by X-ray diffraction patterns, ultraviolet-visible diffuse reflection spectra, scanning electron microscope, and photoluminescence spectra. It was found that the extension of milling time, increase in grinding speed, and suitable dispersant favored the reduced particles size and crystallinity, and enlarged band gap energies, thus benefiting the separation of charge carriers and photocatalytic removal of NO under visible light. Under the suitable condition, the best prepared candidate could removal NO molecules about 45% upon visible light irradiation. Eventually, the good conservation of photocatalytic performance and structural stability identified the robust nature of prepared samples, and a possible photocatalysis mechanism was proposed.

关键词： WO3 ball milling variable parameters photocatalytic NO removal

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Study on helical hole-making process of CFRP/Al alloy laminated materials

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INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 2022年第9-10期121卷 6551-6568页

作者： Li, Xue Jiao, Anyuan Liu, Binghong Zhang, Yue Liu, Guojun Zhang, Zhen Univ Sci & Technol Liaoning Coll Mech Engn & Automat Anshan 114041 Peoples R China Seuic Technol Co Ltd Nanjing 211800 Peoples R China

To ensure assembly accuracy and efficiency, the holes are made directly on the laminated material composed of CFRP and Al alloys. However, due to the sudden change of axial force in the transition area with different laminated sequence, a method of micro-lifting tool was proposed. First, the motion of helical milling was analyzed. The level values of influence the quality of the hole-making are determined, such as spindle speed, pitch, and preload. The response surface method (RSM) was used to design experiments, and the burr height between Al alloy interlayer and the tear value of CFRP was used as the standard to analyze the experimental results. The optimal parameter combination for different laminated sequences were predicted and used for cutting force analysis. The results show that sudden increase in cutting force is prone to occur in the transition area. Secondly, the hole-making processes with variable parameters study were carried out, and the method of micro-lifting tool is proposed for the experimental study of the sudden change of axial force in the transition between interlayer with constant parameters. The results show that the aperture of the hole-making with variable parameters of the laminated materials using the optimal process parameters all meets the H9. The interlayer burr of the Al alloy and the tear value of the CFRP at the entrance and exit conform to the technical requirements. The hole-making axial forces of CFRP and Al alloy are less than 50 N and 60 N, which are 70% and 83% of constant parameters milling.

关键词： Helical milling Response surface method (RSM) variable parameters Micro-lifting tool

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A global path planning algorithm based on the feature map

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IET Cyber-Systems and Robotics 2022年第1期4卷 15-24页

作者： Gongchang Ren Peng Liu Zhou He College of Mechanical and Electrical Engineering Shaanxi University of Science and TechnologyXi'anChina School of Electrical and Control Engineering Shaanxi University of Science and TechnologyXi'anChina

The feature map is a characteristic of high computational efficiency,but it is seldom used in path planning due to its lack of expression of environmental *** solve this problem,a global path planning algorithm based on the feature map is proposed based on the directionality of line segment ***,the robot searches the path along the direction of the target position but turns to search in the direction parallel to the obstacle,which it approaches until the line between the robot and the target position does not intersect with *** it turns to the target position,keep searching the ***,the problems of the direction selection of turning point,corner point and obstacle circumvention in the searching process are analysed and corresponding solutions are put ***,a path optimisation algorithm with variable parameters is proposed,making the optimised path shorter and *** experiments demonstrate that the proposed algorithm is superior to A*algorithm in terms of computation time and path length,especially of the computation efficiency.

关键词： A*algorithm feature map global path planning path optimisation variable parameters

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An Impulse Resistance Current Control Method Suitable for Mobile Energy Storage System

An Impulse Resistance Current Control Method Suitable for Mo...

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2025 International Conference on Electrical Automation and Artificial Intelligence, ICEAAI 2025

作者： Yu, Haojie Yin, Shi Wang, Yaoxuan Sun, Lijing Xiao, Fei State Grid Shanghai Energy Interconnection Research Institute Co. Ltd. Shanghai China State Grid Shanghai Electric Power Co. Ltd. Shanghai China

ISBN: (纸本)9798331506797

The mobile energy storage system has the advantages of environmental friendliness, high power supply quality and two-way interaction with the power grid, and is widely used in application scenarios such as power protection for important loads and temporary power supply. However, compared with the traditional diesel-generating unit, the mobile energy storage system outputs through the power electronic interface, and its overload capacity is limited, and when there are impact loads such as motors and transformers with short-term high-rate current characteristics in the load, it may lead to the collapse of the entire off-grid power supply system. At present, in order to meet the power demand of impact loads, it is often used to increase the capacity of power electronic equipment or to adopt the current inner loop output current limiting mode in the control strategy, but the first mode increases the cost of the mobile energy storage system, and the second mode needs to be targeted with load starting, which has a narrow adaptation range, and it is easy to cause system oscillation in the process of load switching. In this paper, an anti-impulse load control algorithm suitable for mobile energy storage system is proposed, which can automatically correct the voltage control instructions and voltage control parameters according to the magnitude of the load current, effectively suppress the impulse current in the process of impulse load switching, and automatically restore the output voltage after the current stabilizes. This control method can further improve the load capacity of the off-grid power supply system and ensure the stable operation of the off-grid system without increasing the hardware cost of the equipment. © 2025 IEEE.

关键词： Current Suppression Impact loads Impulse Current Mobile Energy Storage variable parameters

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