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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

A Comprehensive Review on Charging Topologies and Power Electronic Converter Solutions for Electric Vehicles

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 675-694页

作者： Abdelfatah Ali Hossam H.H.Mousa Mostafa F.Shaaban Maher A.Azzouz Ahmed S.A.Awad the Department of electrical engineering American University of Sharjah26666 SharjahUnited Arab Emirates the Department of electrical engineering South Valley University83523 QenaEgypt the Department of electrical and computer engineering University of WindsorWindsorON N9B 3P4 Canada electrical engineering Department Qatar UniversityDoha 2713Qatar Department of electrical and computer engineering Sultan Qaboos UniversityMuscat123Oman

Electric vehicles(EVs)are becoming more popular worldwide due to environmental concerns,fuel security,and price *** performance of EVs relies on the energy stored in their batteries,which can be charged using either AC(slow)or DC(fast)***,EVs can also be used as mobile power storage devices using vehicle-to-grid(V2G)*** electronic converters(PECs)have a constructive role in EV applications,both in charging EVs and in ***,this paper comprehensively investigates the state of the art of EV charging topologies and PEC solutions for EV *** examines PECs from the point of view of their classifications,configurations,control approaches,and future research prospects and their impacts on power *** can be classified into various topologies:DC-DC converters,AC-DC converters,DC-AC converters,and AC-AC *** address the limitations of traditional DC-DC converters such as switching losses,size,and high-electromagnetic interference(EMI),resonant converters and multiport converters are being used in high-voltage EV ***,power-train converters have been modified for high-efficiency and reliability in EV *** paper offers an overview of charging topologies,PECs,challenges with solutions,and future trends in the field of the EV charging station applications.

关键词： Charging station charging topology electric vehicle power electronic converter vehicle-to-grid

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Broadband bidirectional Brillouin–Raman random fiber laser with ultra-narrow linewidth

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Chinese Physics B 2024年第2期33卷 371-376页

作者：杨茜李阳邹辉梅杰徐恩明张祖兴 Advanced Photonic Technology Laboratory College of Electronic and Optical Engineering&College of MicroelectronicsNanjing University of Posts and TelecommunicationsNanjing 210023China

We present a Brillouin–Raman random fiber laser(BRRFL)with full-open linear cavity structure to generate broadband Brillouin frequency comb(BFC)with double Brillouin-frequency-shift *** incorporation of a regeneration portion consisting of an erbium-doped fiber and a single-mode fiber enables the generation of broadband *** dynamics of broadband BFC generation changing with the pump power(EDF and Raman)and Brillouin pump(BP)wavelength are investigated in detail,*** suitable conditions,the bidirectional BRRFL proposed can produce a flatamplitude BFC with 40.7-nm bandwidth ranging from 1531 nm to 1571.7 nm,and built-in 242-order Brillouin Stokes lines(BSLs)with double Brillouin-frequency-shift ***,the linewidth of single BSL is experimentally measured to be about 2.5 *** broadband bidirectional narrow-linewidth BRRFL has great potential applications in optical communication,optical sensing,spectral measurement,and so on.

关键词： random laser fiber laser stimulated Brillouin scattering(SBS) stimulated Raman scattering(SRS)

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WebFLex:A Framework for Web Browsers-Based Peer-to-Peer Federated Learning Systems Using WebRTC

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computers, Materials & Continua 2024年第3期78卷 4177-4204页

作者： Mai Alzamel Hamza Ali Rizvi Najwa Altwaijry Isra Al-Turaiki Department of computer Science College of Computer and Information SciencesKing Saud UniversityRiyadhKingdom of Saudi Arabia Department of computer Science and engineering Punjab Engineering CollegeChandigarhIndia

Scalability and information personal privacy are vital for training and deploying large-scale deep learning *** learning trains models on exclusive information by aggregating weights from various devices and taking advantage of the device-agnostic environment of web ***,relying on a main central server for internet browser-based federated systems can prohibit scalability and interfere with the training process as a result of growing client ***,information relating to the training dataset can possibly be extracted from the distributed weights,potentially reducing the privacy of the local data used for *** this research paper,we aim to investigate the challenges of scalability and data privacy to increase the efficiency of distributed training *** a result,we propose a web-federated learning exchange(WebFLex)framework,which intends to improve the decentralization of the federated learning *** is additionally developed to secure distributed and scalable federated learning systems that operate in web browsers across heterogeneous ***,WebFLex utilizes peer-to-peer interactions and secure weight exchanges utilizing browser-to-browser web real-time communication(WebRTC),efficiently preventing the need for a main central *** has actually been measured in various setups using the MNIST *** results show WebFLex’s ability to improve the scalability of federated learning systems,allowing a smooth increase in the number of participating devices without central data *** addition,WebFLex can maintain a durable federated learning procedure even when faced with device disconnections and network ***,it improves data privacy by utilizing artificial noise,which accomplishes an appropriate balance between accuracy and privacy preservation.

关键词： Federated learning web browser privacy deep learning

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

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Electron beam lithography on nonplanar and irregular surfaces

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Microsystems & Nanoengineering 2024年第2期10卷 1-23页

作者： Chenxu Zhu Huseyin Ekinci Aixi Pan Bo Cui Xiaoli Zhu Department of electrical and computer engineering and Waterloo Institute for Nanotechnology(WIN) University of WaterlooWaterlooONCanada

E-beam lithography is a powerful tool for generating nanostructures and fabricating nanodevices with fine features approaching a few nanometers in ***,alternative approaches to conventional spin coating and development processes are required to optimize the lithography procedure on irregular *** this review,we summarize the state of the art in nanofabrication on irregular substrates using e-beam *** overcome these challenges,unconventional methods have been *** instance,polymeric and nonpolymeric materials can be sprayed or evaporated to form uniform layers of electron-sensitive materials on irregular ***,chemical bonds can be applied to help form polymer brushes or self-assembled monolayers on these *** addition,thermal oxides can serve as resists,as the etching rate in solution changes after e-beam ***,e-beam lithography tools can be combined with cryostages,evaporation systems,and metal deposition chambers for sample development and lift-off while maintaining low *** nanopyramids can be fabricated on an AFM tip by utilizing ice as a positive ***,Ti/Au caps can be patterned around a carbon ***,3D nanostructures can be formed on irregular surfaces by exposing layers of anisole on organic ice surfaces with a focused *** advances in e-beam lithography on irregular substrates,including uniform film coating,instrumentation improvement,and new pattern transferring method development,substantially extend its capabilities in the fabrication and application of nanoscale structures.

关键词： lithography beam coating

Elite Dung Beetle Optimization Algorithm for Multi-UAV Cooperative Search in Mountainous Environments

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Journal of Bionic engineering 2024年第4期21卷 1677-1694页

作者： Xiaoyong Zhang Wei Yue The college of Marine electrical engineering Dalian Maritime UniversityDalian116026China

This paper aims to address the problem of multi-UAV cooperative search for multiple targets in a mountainous environment,considering the constraints of UAV dynamics and prior environmental ***,using the target probability distribution map,two strategies of information fusion and information diffusion are employed to solve the problem of environmental information inconsistency caused by different UAVs searching different areas,thereby improving the coordination of UAV ***,the task region is decomposed into several high-value sub-regions by using data clustering *** on this,a hierarchical search strategy is proposed,which allows precise or rough search in different probability areas by adjusting the altitude of the aircraft,thereby improving the search ***,the Elite Dung Beetle Optimization Algorithm(EDBOA)is proposed based on bionics by accurately simulating the social behavior of dung beetles to plan paths that satisfy the UAV dynamics constraints and adapt to the mountainous terrain,where the mountain is considered as an obstacle to be ***,the objective function for path optimization is formulated by considering factors such as coverage within the task region,smoothness of the search path,and path *** effectiveness and superiority of the proposed schemes are verified by the simulation.

关键词： Mountainous environment Multi-UAV cooperative search Environment information consistency Elite dung beetle optimization algorithm(EDBOA) Path planning

Complex-frequency waves:beat loss and win sensitivity

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Light(Science & Applications) 2024年第2期13卷 181-183页

作者： Qingqing Cheng Tao L School of optical-electrical and computer engineering University of Shanghai for Science and TechnologyShanghai200093China Department of Respiratory Diseases and Critical Medicine Quzhou Hospital Affiliated to Wenzhou Medical UniversityQuzhou324000China National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesNanjing UniversityNanjing210093China

Recent experiments have demonstrated that synthesized complex-frequency waves can impart a virtual gain to molecule sensing systems,which can effectively restore information lost due to intrinsic molecular *** enhancement notably amplifies the signal of trace molecular vibrational fingerprints,thereby substantially improving the upper limit of sensitivity.

关键词： thereby Complex limit

Distributed Event-triggered Control for Frequency Restoration in Islanded Microgrids with Reduced Trigger Condition Checking

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 2156-2165页

作者： Yulin Chen Donglian Qi Zhenming Li Zhenyu Wang Xinyi Yang Jianliang Zhang college of electrical engineering Zhejiang UniversityHangzhou 310027China

For islanded microgrids(MGs),distributed control is regarded as a preferred alternative to centralized control for the frequency restoration of ***,distributed control with successive communication restricts the efficiency and resilience of the control *** address this issue,this paper proposes a distributed event-triggered control strategy for the frequency secondary control in islanded *** proposed event-triggered control is Zeno behavior free and enables each DG to update and propagate its state to neighboring DGs only when a specific“event”occurs,which significantly reduces the communication *** with the existing event-triggered control,a trigger condition checking period of the proposed event-triggered control is provided to reduce the computation burden when checking the trigger ***,using the aperiodicity and intermittent properties of the communication,a simple detection principle is proposed to detect and isolate the compromised communication links in a timely and economic fashion,which improves the resilience of the system against FDI ***,the control effectiveness of the proposed control scheme is validated by the simulation results of the tests on an MG with 4 DGs.

关键词： Distributed control event-triggered control islanded microgrid secondary control

Stability Investigation and Improvement for DC Cascade Systems with Simplified Impedance-based Stability Criterion

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1044-1052页

作者： Junbin Fang Zhikang Shuai Yang Li Zhibing Wang Xiangyang Wu Xia Shen Z.John Shen college of electrical and Information engineering Hunan UniversityChangsha 410082China Renewable Energy Department of China Electric Power Research Institute Beijing 100192China Department of electrical and computer engineering Illinois Institute of TechnologyChicagoIL 60616USA IEEE

In DC distributed power systems(DPSs),the complex impedance interactions possibly lead to DC bus voltage oscillation or *** previous research,the stability analysis of DPSs is implemented based on mathematical analysis in control *** specific mechanisms of the instability of the cascade system have not been intuitively *** this paper,the stability analysis of DPSs based on the traditional Nyquist criterion is simplified to the resonance analysis of the seriesconnected port impedance(Z=R+jX)of source and load *** reveals that the essential reason for impedance instability of a DC cascade system is that the negative damping characteristic(R<0)of the port the overall impedance amplifies the internal resonance source at reactance zero-crossing *** simplified stability criterion for DC cascade systems can be concluded as:in the negative damping frequency ranges(R<0),there exists no zero-crossing point of the reactance component(i.e.,X=0).According to the proposed stability criterion,the oscillation modes of cascade systems are classified.A typical one is the internal impedance instability excited by the negative damping,and the other one is that the external disturbance amplified by negativity in a low stability ***,the impedance reshaping method for stability improvement of the system can be further *** validity of the simplified criterion is verified theoretically and experimentally by a positive damping reshaping method.

关键词： DC cascaded system,impedance model impedance reconstruction stability criterion