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Chinese Journal of Aeronautics 2024年第4期37卷 556-573页

作者： Baoqi CHANG Zhaoxi YI Fen ZHANG Lian duan Ji-an duan school of Mechanical and electrical engineering Central South UniversityChangsha 410083China State Key Laboratory of High Performance and Complex Manufacturing Central South UniversityChangsha 410083China school of Physics and electronics Central South UniversityChangsha 410083China

To improve the service and machining performance of the workpiece, the tool wear mechanisms, surface machining quality, and wear resistance in conventional side milling(CSM)and longitudinal-torsional ultrasonic vibration side milling(LTUVSM) of GH4169 superalloy at different cutting lengths are investigated systematically. Tool wear mechanisms are revealed and the correlation between machined surface quality with tool wear is analyzed correspondingly. Tool wear patterns mainly include adhesive wear, diffusion wear, abrasive wear, and chipping *** surface quality is achieved in LTUVSM due to a maximum reduction of flank wear bandwidth and wear rate by 71.9% and 71.5%, respectively, compared to CSM. The friction coefficient,initial wear stage time, and wear volume of dry sliding wear were measured to evaluate the workpiece wear resistance. The maximum reductions in friction coefficient and wear volume in LTUVSM are 18.2% and 15.8% compared to CSM. The regular ultrasonic vibration textures suppress the friction and the growth of contact nodes in the contact area, decreasing the degree of surface wear, which is demonstrated by a 38.8% increase in initial wear stage time compared to *** conclusion, the workpiece in LTUVSM exhibits higher wear resistance because of the improvement of tool wear and the guarantee of surface quality.

关键词： Dry sliding wear Surface quality Tool wear Ultrasonic vibration Wear resistance

Open-loop Phase Synchronization Method of Positive and Negative Sequences for Three-phase Asymmetric Grid

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CSEE Journal of Power and Energy Systems 2023年第5期9卷 1973-1979页

作者： Jian He shanxu duan State Key Laboratory of Advanced Electromagnetic engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Currently,a grid-connected inverter is required to inject a dual-sequence current during asymmetric grid sags,which means both positive and negative sequence phases should be *** paper proposes an open-loop phase synchronization(OLS)method of positive and negative sequences for an asymmetric grid based on the moving average filter(MAF),which does not need to separate the positive and negative sequence fundamental components of grid *** a benefit,there is no double-frequency oscillation in the estimated phases at offnominal frequencies since the positive and negative sequence phases are obtained *** proposed method not only has the inherent advantages of OLS,but also further improves the dynamic response since the window length of MAF is only 1/6 of the fundamental *** effectiveness of the proposed OLS is verified by experimental results.

关键词： Asymmetric grid open-loop synchronization positive and negative sequence phases

Exploring the Mechanism,Advancements,and Application of Thermogalvanic Effect in Hydrogels

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Chinese Journal of Chemistry 2024年第5期42卷 543-556页

作者： Xiaoyu Yang Peng Wang Xiaolong Wu Yongli Liao Senyun Liu Wei duan Ying Yue school of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBaodingHebei071000 China Hebei Key Laboratory of Electric Machinery Health Maintenance & Failure Prevention North China Electric Power UniversityBaodingHebei071003 China Electric Power Research Institute China South Power GridGuangzhouGuangdong510000 China Key Laboratory of Icing and Anti/De-icing China Aerodynamics Research and Development CenterMianyangSichuan621000 China

The issue of energy consumption has garnered significant interest due to its excessive ***,thermoelectric devices have been getting increased attention,as they can harness waste heat from various sources,such as solar radiation,human body,and industrial ***,the recovery of low-grade heat has been a challenge,resulting in unsustainable energy use and significant *** considerable advances have been made in thermoelectric materials in recent decades,the majority of these devices still primarily employ ***,the emergence of quasi-solid-state thermoelectric materials represents a novel development with profound promise for the environment and *** materials offer several advantages,such as improved energy conversion capacities,cost-effectiveness,versatility,and scalability,to support increased ***,this review explores the application of thermoelectric materials in self-powered sensors,integrated modules,and heat harvesting ***,the potential of high-performance thermocouples based on thermogalvanic effects is assessed,along with the challenges that must be overcome to realize this goal.

关键词： Hydrogel Thermogalvanic effect Thermochemistry Electrolytes Flexible electronics

Mechanical and magnetocaloric adjustable properties of Fe3O4/PET deformed nanoparticle film

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Chinese Physics B 2024年第3期33卷 589-595页

作者：范凤国段林彤 school of Physics and electrical Information Shangqiu Normal UniversityShangqiu 476000China

The flexibility of nanoparticle films is a topic of rapidly growing interest in both scientific and engineering researches due to their numerous potential applications in a broad range of wearable electronics and biomedical *** article presents the elucidation of the properties of nanoparticle ***,a flexible film is fabricated based on polyethylene terephthalate(PET)and magnetic iron oxide at the nanoscale using layer-by-layer *** 2D thin flexible film material can be bent at different angles from 0°to 360°.With an increase in elastic deformation angles,the magnetocaloric effect of the film gradually increases in the alternating magnetic *** test results from a vibrating sample magnetometer and a low-frequency impedance analyzer demonstrate that the film has a good magnetic response and *** magnetocaloric effect and magnetic induction effect are controlled by deformation,providing a new idea for the application of elastic *** combines the flexibility of the nanoparticle PET substrate and,in the future,it may be used for skin adhesion for administration and magnetic stimulation control.

关键词： nanoparticle film deformation magnetic properties flexible substrates

EMCO-based Optimal Layout Design of Hybrid Wind-wave Energy Converters Array

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Protection and Control of Modern Power Systems 2024年第5期9卷 142-161页

作者： Bo Yang Jinhang duan Yunfeng Yan Bingqiang Liu Jianxiang Huang Lin Jiang Rui Han Faculty of Electric Power engineering Kunming University of Science and TechnologyKunming 650500China College of electrical engineering Zhejiang UniversityHangzhou 310027China Company of Kunming Bureau of CSG EHV Transmission Company Kunming 650217China school of electrical engineering and electronics University of LiverpoolLiverpool L693GJUK Company of Electric Power Science Research Institute State Grid Zhejiang Electric Power Company Ltd.Hangzhou 310014China

Marine renewable energy,combining wave energy converters(WECs)and floating wind turbines(FWTs)into hybrid wave-wind energy converters(HWWECs),garners significant global *** offer potential cost reductions,increased power generation,and enhanced system *** absorption power of high wind energy sites is primarily influenced by the complex hydrodynamic interactions among floating bodies,which are closely related to the location and wind-wave environment of high wind energy *** delve into the positive interactions among HWWECs,this paper proposes a HWWEC array optimization strategy based on the artificial ecosystem opti-mization-manta ray foraging optimization coordinated op-timizer(EMCO).In EMCO,the decomposition operator of artificial ecosystem optimization(AEO)and the flip-ping-dipper foraging operator of manta ray foraging opti-mization coordinated(MRFO)cooperate dynamically to effectively balance local exploitation and global *** validate the effectiveness of EMCO,experiments were conducted in scenarios with 3,5,8,and 20 HWWECs,and compared with five typical *** results demonstrate the existence of multiple optimal solutions for HWWEC *** achieves maximum total absorp-tion power and exhibits good ***,EMCO en-hances the q-factor values of HWWECs across four scales:1.0478,1.0586,1.0612,and 0.9965,*** Terms—Marine renewable energy,hybrid wind-wave energy converter,layout optimization,coordinating optimizer.

关键词： Marine renewable energy hybrid wind-wave energy converter layout optimization coordinating optimizer

Simplified Analytical Model for Estimation of Switching Loss of Cascode GaN HEMTs in Totem-pole PFC Converters

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Chinese Journal of electrical engineering 2019年第3期5卷 1-9页

作者： Qiqi Li Bangyin Liu shanxu duan State Key Laboratory of Advanced Electromagnetic engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

A practical analytical model to calculate the switching loss of cascode gallium nitride high electron mobility transistors(GaN HEMTs)is *** facilitate analysis and application,the transmission delays introduced by Si MOSFET and interconnection inductances are ignored in ***,the nonlinear junction capacitances of the device and circuit stray inductances are also incorporated to increase the accuracy of the *** turn-on and turn-off switching processes are described in detail and the simplified equations can be easily solved by using mathematical *** on the analytical model,loss evaluation of totem-pole PFC converter is introduced ***,the accuracy of the model is validated by comparing the calculated loss and converter’s efficiency with experiment *** efficiency of 99.26%is achieved for a 3.6 kW single phase CCM Totem-Pole PFC AC/DC converter switching at 50 kHz based on 650 V cascode GaN HEMTs.

关键词： Analytical model cascode GaN HEMTs totem-pole PFC efficiency evaluation

Enhanced UAV Pursuit-Evasion Using Boids Modelling:A Synergistic Integration of Bird Swarm Intelligence and DRL

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Computers, Materials & Continua 2024年第9期80卷 3523-3553页

作者： Weiqiang Jin Xingwu Tian Bohang Shi Biao Zhao Haibin duan Hao Wu school of Information and Communications engineering Faculty of Electronic and Information EngineeringXi’an Jiaotong UniversityXi’an710049China China Academy of electronics and Information Technology China Electronics Technology Group Corporation(CETC)Beijing100041China Department ofAutomatic Control School of Automation Science and Electrical EngineeringBeihangUniversityBeijing100191China

TheUAV pursuit-evasion problem focuses on the efficient tracking and capture of evading targets using unmanned aerial vehicles(UAVs),which is pivotal in public safety applications,particularly in scenarios involving intrusion monitoring and *** address the challenges of data acquisition,real-world deployment,and the limited intelligence of existing algorithms in UAV pursuit-evasion tasks,we propose an innovative swarm intelligencebased UAV pursuit-evasion control framework,namely“Boids Model-based DRL Approach for Pursuit and Escape”(Boids-PE),which synergizes the strengths of swarm intelligence from bio-inspired algorithms and deep reinforcement learning(DRL).The Boids model,which simulates collective behavior through three fundamental rules,separation,alignment,and cohesion,is adopted in our *** integrating Boids model with the Apollonian Circles algorithm,significant improvements are achieved in capturing UAVs against simple evasion *** further enhance decision-making precision,we incorporate a DRL algorithm to facilitate more accurate strategic *** also leverage self-play training to continuously optimize the performance of pursuit *** experimental evaluation,we meticulously designed both one-on-one and multi-to-one pursuit-evasion scenarios,customizing the state space,action space,and reward function models for each *** simulations,supported by the PyBullet physics engine,validate the effectiveness of our proposed *** overall results demonstrate that Boids-PE significantly enhance the efficiency and reliability of UAV pursuit-evasion tasks,providing a practical and robust solution for the real-world application of UAV pursuit-evasion missions.

关键词： UAV pursuit-evasion swarm intelligence algorithm Boids model deep reinforcement learning self-play training

Centralized control of parallel connected power conditioning system in electric vehicle charge-discharge and storage integration station

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Journal of Modern Power Systems and Clean Energy 2015年第2期3卷 269-276页

作者： Jiuqing CAI Changsong CHEN Peng LIU shanxu duan State Key Laboratory of Advanced Electromagnetic engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhanChina

This study presents a centralized control scheme that coordinates parallel operations of power conditioning system(PCS)for the grid interactions of electric vehicles(EVs)in EV charge-discharge and storage integration *** issues for the control and operation of PCS under various operation modes are discussed,including vehicle to grid(V2G)mode,stand-alone mode and seamless transfer *** intelligent multi-mode charge-discharge method is utilized for the V2G mode,and the parallel control method based on communication network is adopted for the standalone *** addition,a novel seamless transfer strategy is proposed,which is able to implement PCS transition between V2G mode and stand-alone *** detailed process of the seamless transfer between the two modes is *** results are presented to show the performance and feasibility of this strategy.

关键词： Centralized control Power conditioning system(PCS) Charge-discharge and storage integration station Vehicle to grid(V2G) Seamless transfer

Perpendicularly assembled oriented electrospinning nanofibers based piezoresistive pressure sensor with wide measurement range

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Nano Research 2024年第7期17卷 6493-6501页

作者： Xiaoxue Bi Zhigang duan Xiaojuan Hou Shuo Qian Mengjiao Yuan Jiajun Hu Jie Zhang Yuchen Lu Yanli Liu Jian He Zhiling Peng Xiujian Chou school of Mechanical and electrical engineering North University of ChinaTaiyuan 030051China Science and Technology on Electronic Test and Measurement Laboratory North University of ChinaTaiyuan 030051China school of Software North University of ChinaTaiyuan 030051China school of Information and Communication engineering North University of ChinaTaiyuan 030051China

With the rapid development of wearable electronics,flexible pressure sensors have attracted wide attention in human–computer interaction and intelligent ***,it is a challenge to achieve a sensor with high sensitivity,wide measurement range,and wearing ***,we develop an oriented electrospinning thermoplastic polyurethane/polyacrylonitrile(TPU/PAN)nanofibers(OETPN)based piezoresistive pressure sensor(PONPS)in which the active layer and the electrode are assembled *** interdigital electrode is fabricated by spraying silver nanowires(AgNWs)on the OETPN through a mask *** active layer is composed of OETPN coated with MXene,encapsulated on the electrode by polyurethane(PU)*** porous structure of nanofibers membrane broadens the measurement range of the *** oriented nanofibers as active layer can improve the sensitivity in low pressure,because oriented nanofibers without interweaving nanofibers are more compressible than disordered *** prepared using the spraying method creates nanoscale microstructure and increases *** perpendicular assembly has greater response between the active layer and the electrode than the parallel assembly to improve the *** sensor exhibits high sensitivity(6.71 kPa^(−1),0.02–2 kPa)and wide measurement range(0.02–700 kPa).The sensor can detect weak signals such as radial artery.A pressure array constructed precisely represents the distribution of *** intelligent throat is created by combining machine learning algorithms with the *** can detect and recognize subtle throat vibrations while speaking,achieving recognition accuracy up to 100%using support vector machine(SVM)for five words with different *** fabricated sensor shows promising prospects in personal healthcare and intelligent robots.

关键词： oriented nanofibers perpendicular assembly parallel assembly intelligent throat machine learning algorithms