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Chinese Journal of mechanical engineering 2024年第3期37卷 1-25页

作者： Xiaolin Tang Jiaxin Chen Yechen Qin Teng Liu Kai Yang Amir Khajepour Shen Li college of mechanical and Vehicle engineering Chongqing UniversityChongqing 400044China School of mechanical engineering Beijing Institute of TechnologyBeijing 100081China Department of mechanical and mechatronics engineering University of WaterlooWaterlooON N2L 3G1Canada School of Civil engineering Tsinghua UniversityBeijing 100084China

The new energy vehicle plays a crucial role in green transportation,and the energy management strategy of hybrid power systems is essential for ensuring energy-efficient *** paper presents a state-of-the-art survey and review of reinforcement learning-based energy management strategies for hybrid power ***,it envisions the outlook for autonomous intelligent hybrid electric vehicles,with reinforcement learning as the foundational *** of all,to provide a macro view of historical development,the brief history of deep learning,reinforcement learning,and deep reinforcement learning is presented in the form of a ***,the comprehensive survey and review are conducted by collecting papers from mainstream academic *** most of the contributions based on three main directions—algorithm innovation,powertrain innovation,and environment innovation—provides an objective review of the research ***,to advance the application of reinforcement learning in autonomous intelligent hybrid electric vehicles,future research plans positioned as“Alpha HEV”are envisioned,integrating Autopilot and energy-saving control.

关键词： New energy vehicle Hybrid power system Reinforcement learning Energy management strategy

Aero-Hydro-Elastic-Servo Modeling and Dynamic Response Analysis of A Monopile Offshore Wind Turbine Under Different Operating Scenarios

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China Ocean engineering 2024年第3期38卷 379-393页

作者： XIE Shuang-yi GAO Jian LI Yong-ran JIANG Shu-xin ZHANG Cheng-lin HE Jiao college of mechanical engineering Chongqing University of TechnologyChongqing 400044China Beijing Institute of Precision mechatronics and Controls Beijing 100076China college of mechanical and Vehicle engineering Chongqing UniversityChongqing 400044China Fishery Machinery and Instrument Research Institute Chinese Academy of Fishery SciencesShanghai 200092China School of mechanical and Power engineering Chongqing University of Science&TechnologyChongqing 401331China

This paper constructs a coupled aero-hydro-elastic-servo simulation framework for a monopile offshore wind turbine(OWT).In this framework,a detailed multi-body dynamics model of the monopile OWT including the gearbox,blades,tower and other components(nacelle,hub,bedplate,etc.)has been explicitly *** effects of pile−soil interaction,controller and operational conditions on the turbine dynamic responses are studied systematically in time domain and frequency *** results show that(1)a comprehensive drivetrain model has the capability to provide a more precise representation of the complex dynamic characteristics exhibited by drivetrain components,which can be used as the basis for further study on the dynamic characteristics of the drivetrain.(2)The pile−soil interaction can influence the wind turbine dynamic responses,particularly under the parked condition.(3)The effect of the pile−soil interaction on tower responses is more significant than that on blade responses.(4)The use of the controller can substantially affect the rotor characteristics,which in turn influences the turbine dynamic responses.(5)The tower and blade displacements under the operational condition are much larger than those under the parked *** model and methodology presented in this study demonstrate potential for examining complex dynamic behaviors of the monopile *** ensure accuracy and precision,it is imperative to construct a detailed model of the wind turbine system,while also taking into account simulation efficiency.

关键词： offshore wind turbine(OWT) pile−soil interaction dynamic response parked condition operating condition

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Absence of ultrasonic-vibration-induced plasticity in metallic glacial glasses

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Rare Metals 2024年第7期43卷 3422-3429页

作者： Zhe Chen Shuai Ren Jian Zhu Jie Shen Xin Li He-Ting Zhang Hong-Ji Lin Sajad Sohrabi Wen-Qing Ruan Zhen-Xuan Zhang Xiong Liang Jiang Ma Jun Shen Shenzhen Key Laboratory of High Performance Nontraditional Manufacturing College of Mechatronics and Control EngineeringShenzhen University Institute of Physics Chinese Academy of Sciences School of mechanical Electrical and Information EngineeringShandong University

Metallic glasses (MGs) have been found to exhibit unexpected ultrasonic-vibration-induced plasticity (UVIP),which provides a promising way to realize room temperature processing and molding of ***,whether all MGs poss... 详细信息

关键词： Metallic glass

Effect of nitrile butadiene rubber hardness on the sealing characteristics of hydraulic O-ring rod seals

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2024年第1期25卷 63-78页

作者： Xiaoxuan LI Bingqing WANG Xudong PENG Yuntang LI Xiaolu LI Yuan CHEN Jie JIN college of Quality and Safety engineering China Jiliang UniversityHangzhou310018China college of mechanical and Electrical engineering China Jiliang UniversityHangzhou310018China college of mechanical engineering Zhejiang University of TechnologyHangzhou310023China

The nitrile butadiene rubber(NBR)hardness effect on the sealing characteristics of hydraulic O-ring rod seals is analyzed based on a mixed lubrication elastohydrodynamic *** studies are conducted to reveal the mechanism of the influence of rubber hardness on the static and dynamic behavior of *** optimized selections of rubber hardness are then investigated under different *** show that the low hardness seal is prone to stress concentration due to the extrusion effect under high pressure conditions;it is also more prone to leaking.A high hardness seal can better prevent leakage by reducing film thickness but it will cause large frictional power loss and increase the probability of wear *** choice of low hardness is recommended to reduce friction with the premise that leakage requirements are met.

关键词： Nitrile butadiene rubber(NBR)hardness Sealing characteristics Optimized selection O-ring seal

Churning loss characteristics of a wet three-phase high-speed reluctance motor

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2024年第3期25卷 251-267页

作者： Zhenzhou ZHANG Mingzhu DAI Chenchen ZHANG Yi CHEN Bin MENG college of mechanical engineering Zhejiang University of TechnologyHangzhou 310023China

With the increasing requirements of electro-hydrostatic actuators(EHAs)for power,volume,and pressure,there is a growing tendency in the industry to combine the motor and pump to form a so-called'motor pump'to improve the *** this paper,a novel structure for a wet three-phase high-speed reluctance motor pump is proposed,which can further improve integration by removing the dynamic seal on the pump shaft,thereby avoiding the problems of dynamic seal wear and oil leakage and improving heat dissipation under high-speed working ***,after the motor is wetted,the churning loss caused by immersion of the rotor in the oil causes additional fluid resistance *** on fundamental fluid mechanics,an analytical model of the churning torque of a wet motor was *** verify the accuracy of the analytical model,a simulation model of churning loss was established based on computational fluid dynamics(CFD),and the churning torque and flow field state were ***,an experimental prototype was designed and manufactured,and a test bench for churning loss was *** oil churning torque was measured at different speeds and *** results from the analytical,simulation,and experimental models agreed *** experimental results validated the analytical model and CFD *** research provides a practical method for calculating the churning loss and serves as guidance for future optimization of churning loss reduction.

关键词： Motor pump Wet motor Churning loss Analytical model Computational fluid dynamics(CFD)

Modeling and analysis of gradient metamaterials for broad fusion bandgaps

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1155-1170页

作者： Changqi CAI Chenjie ZHU Fengyi ZHANG Jiaojiao SUN Kai WANG Bo YAN Jiaxi ZHOU School of mechanical engineering Zhejiang Sci-Tech University School of Material and Environmental engineering Hangzhou Dianzi University college of mechanical and Vehicle engineering Hunan University

A gradient metamaterial with varying-stiffness local resonators is proposed to open the multiple bandgaps and further form a broad fusion bandgap. First, three local resonators with linearly increasing stiffness are periodically attached to the spring-mass chain to construct the gradient metamaterial. The dispersion relation is then derived based on Bloch's theorem to reveal the fusion bandgap theoretically. The dynamic characteristic of the finite spring-mass chain is investigated to validate the fusion of multiple bandgaps. Finally, the effects of the design parameters on multiple bandgaps are discussed. The results show that the metamaterial with a non-uniform stiffness gradient pattern is capable of opening a broad fusion bandgap and effectively attenuating the longitudinal waves within a broad frequency region.

关键词： local resonance mechanism elastic metamaterial stiffness gradient bandgap fusion broadband wave attenuation O321 74H45 74J05

Research on Flexible Job Shop Scheduling Based on Improved Two-Layer Optimization Algorithm

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Computers, Materials & Continua 2024年第1期78卷 811-843页

作者： Qinhui Liu Laizheng Zhu Zhijie Gao Jilong Wang Jiang Li college of mechanical and Electrical engineering Harbin Engineering UniversityHarbin150001China

To improve the productivity,the resource utilization and reduce the production cost of flexible job shops,this paper designs an improved two-layer optimization algorithm for the dual-resource scheduling optimization problem of flexible job shop considering workpiece ***,a mathematical model is established to minimize the maximum completion ***,an improved two-layer optimization algorithm is designed:the outer layer algorithm uses an improved PSO(Particle Swarm Optimization)to solve the workpiece batching problem,and the inner layer algorithm uses an improved GA(Genetic Algorithm)to solve the dual-resource scheduling ***,a rescheduling method is designed to solve the task disturbance problem,represented by machine failures,occurring in the workshop production ***,the superiority and effectiveness of the improved two-layer optimization algorithm are verified by two typical *** case results show that the improved two-layer optimization algorithm increases the average productivity by 7.44% compared to the ordinary two-layer optimization *** setting the different numbers of AGVs(Automated Guided Vehicles)and analyzing the impact on the production cycle of the whole order,this paper uses two indicators,the maximum completion time decreasing rate and the average AGV load time,to obtain the optimal number of AGVs,which saves the cost of production while ensuring the production *** research combines the solved problem with the real production process,which improves the productivity and reduces the production cost of the flexible job shop,and provides new ideas for the subsequent research.

关键词： Dual resource scheduling workpiece batching rescheduling particle swarm optimization genetic algorithm

Adaptive state-constrained/model-free iterative sliding mode control for aerial robot trajectory tracking

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 603-618页

作者： Chen AN Jiaxi ZHOU Kai WANG college of mechanical and Vehicle engineering Hunan UniversityChangsha 410082China Department of mechanical engineering The Hong Kong Polytechnic UniversityHong KongChina

This paper develops a novel hierarchical control strategy for improving the trajectory tracking capability of aerial robots under parameter *** hierarchical control strategy is composed of an adaptive sliding mode controller and a model-free iterative sliding mode controller(MFISMC).A position controller is designed based on adaptive sliding mode control(SMC)to safely drive the aerial robot and ensure fast state convergence under external ***,the MFISMC acts as an attitude controller to estimate the unmodeled dynamics without detailed knowledge of aerial ***,the adaption laws are derived with the Lyapunov theory to guarantee the asymptotic tracking of the system ***,to demonstrate the performance and robustness of the proposed control strategy,numerical simulations are carried out,which are also compared with other conventional strategies,such as proportional-integralderivative(PID),backstepping(BS),and *** simulation results indicate that the proposed hierarchical control strategy can fulfill zero steady-state error and achieve faster convergence compared with conventional strategies.

关键词： aerial robot hierarchical control strategy model-free iterative sliding mode controller(MFISMC) trajectory tracking reinforcement learning

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Blind Signal Reception in Downlink Generalized Spatial Modulation Multiuser MIMO System Based on Minimum Output Energy

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Chinese Journal of Electronics 2024年第2期33卷 504-515页

作者： Wei-Chiang WU college of mechanical and Electrical engineering Sanming University

This paper considers downlink multiuser multiple-input-multiple-output system with parallel spatial modulation scheme, in which base station transmitter antennas are separated into K groups corresponding to K user terminals. Generalized spatial modulation is employed, in which a subset(more than single antenna) of transmit antenna array are activated and the activating pattern corresponds to specific spatial symbol. Different from existing precoding-based algorithms, we develop a two-stage detection scheme at each user terminal: In the pre-processing stage, a minimax algorithm is proposed to identify the indices of active antennas, where the key idea is that the minimum output energy of the detector is maximized; A constrained minimum output energy algorithm is proposed in the post-processing stage to mitigate multiuser interference and extract temporal symbols. Compared with existing precoding-based algorithms, the complexity is significantly reduced. Moreover, the proposed algorithm is semi-blind,in which only a small subset of channel state information is required to identify active antennas as well as eliminate multiuser interference. Simulation results demonstrate that the proposed algorithm is near-far resistant and the spectral efficiency is extensively increased compared to the conventional spatial modulation scheme.

关键词： GSM Spectral efficiency Computer network reliability Transmitting antennas Modulation Symbols Downlink

Calculation and Analysis of TVMS Considering Profile Shifts and Surface Wear Evolution Process of Spur Gear

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Chinese Journal of mechanical engineering 2024年第3期37卷 136-150页

作者： Wenzheng Liu Rupeng Zhu Wenguang Zhou Jingjing Wang college of mechanical and Electrical engineering Nanjing University of Aeronautics and AstronauticsNanjingChina

Profile shift is a highly effective technique for optimizing the performance of spur gear transmission ***,tooth surface wear is inevitable during gear meshing due to inadequate lubrication and long-term *** profile shift and tooth surface wear(TSW)can impact the meshing characteristics by altering the involute tooth *** this study,a tooth stiffness model of spur gears that incorporates profile shift,TSW,tooth deformation,tooth contact deformation,fillet-foundation deformation,and gear body structure coupling is *** model efficiently and accurately determines the time-varying mesh stiffness(TVMS).Additionally,an improved wear depth prediction method for spur gears is developed,which takes into consideration the mutually prime teeth numbers and more accurately reflects actual gear meshing *** show that consideration of the mutual prime of teeth numbers will have a certain impact on the TSW ***,the finite element method(FEM)is employed to accurately verify the values of TVMS and load sharing ratio(LSR)of profile-shifted gears and worn *** study quantitatively analyzes the effect of profile shift on the surface wear process,which suggests that gear profile shift can partially alleviate the negative effects of *** contribution of this study provides valuable insights into the design and maintenance of spur gear systems.

关键词： Profile shift Tooth surface wear Structure coupling effect Improved wear depth prediction method TVMS