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Deployment optimization for target perpetual coverage in energy harvesting wireless sensor network

Digital Communications and Networks 2024年第2期10卷 498-508页

作者： Zhenkun Jin Yixuan Geng Chenlu Zhu Yunzhi Xia Xianjun Deng Lingzhi Yi Xianlan Wang Wuhan Business University 430056China Wuhan Research Institute of Post and Telecommunication Wuhan430074China Hubei Key Laboratory of Distributed System Security Hubei Engineering Research Center on Big Data SecuritySchool of Cyber Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China Hubei Chutian Expressway Digital Technology Co.Ltd Wuhan430074China School of Information and Safety Engineering Zhongnan University of Economics and LawWuhan430073China

Energy limitation of traditional Wireless Sensor Networks(WSNs)greatly confines the network lifetime due to generating and processing massive sensing data with a limited *** energy harvesting WSN is a novel network architecture to address the limitation of traditional ***,existing coverage and deployment schemes neglect the environmental correlation of sensor nodes and external energy with respect to physical *** considering the spatial correlation of the environment and the uneven distribution of energy in energy harvesting WSN,we investigate how to deploy a collection of sensor nodes to save the deployment cost while ensuring the target perpetual *** Confident information Coverage(CIC)model is adopted to formulate the CIC Minimum Deployment Cost Target Perpetual Coverage(CICMTP)problem to minimize the deployed sensor *** the CICMTP is NP-hard,we devise two approximation algorithms named Local Greedy Threshold Algorithm based on CIC(LGTA-CIC)and Overall Greedy Search Algorithm based on CIC(OGSA-CIC).The LGTA-CIC has a low time complexity and the OGSA-CIC has a better approximation *** simulation results demonstrate that the OGSA-CIC is able to achieve lower deployment cost and the performance of the proposed algorithms outperforms GRNP,TPNP and EENP algorithms.

关键词： Energy harvesting WSN Deployment optimization Confident information coverage(CIC) Target perpetual coverage

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Fault-induced gear meshing modulation sideband extraction and evaluation for fault diagnosis of planetary gearboxes

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science China(Technological sciences) 2025年第1期68卷 335-351页

作者： Peng ZHOU Xiaoluo YU Yang YANG Qingbo HE Zhike PENG State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China School of Mechanical Engineering Ningxia UniversityYinchuan 750021China Science and Technology on Vehicle Transmission Laboratory China North Vehicle InstituteBeijing 100072China

Gearboxes,known for their compact size and stable transmission capability,are widely used as power transmission structures in various types of mechanical equipment,such as wind turbines,helicopters,and special ***,due to harsh and non-stationary working conditions,gear surfaces often deteriorate,leading to faults such as wear,pitting,and ***,it is vital to monitor the working status of gearboxes and diagnose gear faults as early as *** faults can induce characteristic modulation effects near the gear meshing frequency(GMF),resulting in the appearance of faultinduced sidebands in a vibration *** of these sidebands allows for the diagnosis of gear faults in a ***,when faced with a planetary gearbox having a complex configuration,strong background noise and additional faultunrelated sidebands can interfere with fault-induced sidebands,making accurate diagnosis *** address these challenging issues,this paper proposes a novel fault-induced gear meshing modulation sideband extraction *** the process,the sidebands directly related to the gear fault near the GMF are first identified and then extracted by a variational harmonic mode decomposition(VHMD)***,a fault-related gear meshing modulation component(GMMC)can be accurately reconstructed by summing up the extracted fault-induced *** the GMMC,the gear fault severity can be assessed by evaluating its amplitude modulation(AM)*** superior performance of the proposed method is finally demonstrated by experimental data.

关键词： planetary gearbox gear meshing frequency modulation sideband signal decomposition fault diagnosis

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Refined modeling and experimental verification of a torque motor for an electro-hydraulic servo valve

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Chinese Journal of Aeronautics 2023年第6期36卷 302-317页

作者： Zhichuang CHEN Shenghong GE Yulei JIANG Wenhao CHENG Yuchuan ZHU National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China Aviation Key Laboratory of Science and Technology on Aero Electromechanical System Integration Nanjing Engineering Institute of Aircraft SystemsNanjing 210061China AVIC Nanjing Servo Control System Co. LtdNanjing 210032China

The Permanent Magnet Torque Motor(PMTM)is the key electro-mechanical conversion device in an Electro-Hydraulic Servo Valve(EHSV).In this work,a refined model of a PMTM is developed,considering the non-working air-gaps between the upper or lower yoke and the armature,the fringing effect at the limiting holes,and the nonlinear permeability of soft magnetic *** on the refined model,the influences of various factors on the calculation accuracy of the magnetic flux at the pole surfaces of the armature and the output torque are *** verifying the validity of the refined model,a Finite Element Analysis(FEA)of the PMTM is conducted,and a test platform is *** with existing models,the refined model can better reveal the intrinsic mechanism of the PMTM,and its calculations are more consistent with the FEA *** experimental results of the armature deflection displacement show that the refined model can accurately describe the output characteristics of the PMTM.

关键词： Calculation accuracy Electro-hydraulic servo valve Experimental verification Finite element analysis Refined model Torque motor

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Lightweight Curve Estimation Method for Low-Light Image Enhancement 7

Lightweight Curve Estimation Method for Low-Light Image Enha...

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7th International Conference on Advanced Algorithms and Control engineering, ICAACE 2024

作者： Yin, Guorong Wang, Lingfeng Li, Haichang Li, Yilun College Of Information Science And Technology Beijing University Of Chemical Technology Beijing100029 China Institute Of Software Chinese Academy Of Sciences Science And Technology On Integrated Information System Laboratory Beijing100190 China

ISBN: (纸本)9798350361445

Low-light image enhancement is an important issue in digital image processing area. However, in practice, it is still a difficult problem, especially how to balance computational cost and restore result. To tackle this difficulty, in this paper, we present a fast curve transition based low-light image enhancement model and propose a new lightweight curve estimation model. Specifically, an extremely lightweight curve estimation network based on parameter curve model is proposed, called LCE. Compared with the traditional method, called Zero-DCE, which utilizes iterative polynomial interpolation, the proposed can estimate the translate curve non-recursively. Benefitting from intuitive and simple nonlinear curve mapping as well as the lightweight curve estimation network, experimental results show that the proposed model is superior to the existing methods in terms of computational cost, while holds similar enhanced results on low-light images. © 2024 IEEE.

关键词： Image enhancement

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Task Planning and Collaboration of Jellyfish-inspired Multiple Spherical Underwater Robots

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Journal of Bionic engineering 2022年第3期19卷 643-656页

作者： Ruochen An Shuxiang Guo Yuanhua Yu Chunying Li Tendeng Awa Graduate School of Engineering Kagawa UniversityTakamatsuKagawa761-0396Japan Key Laboratory of Convergence Medical Engineering System and Healthcare Technology The Ministry of Industry and Information TechnologySchool of Life Science and TechnologyBeijing Institute of TechnologyBeijing100081China School of Life Science and Technology Changchun University of Science and TechnologyChangchun130022China

Task planning and collaboration of multiple robots have broad application prospects and value in the field of *** improve the performance and working efficiency of our Spherical Underwater Robot(SUR),we propose a multi-robot control strategy that can realize the task planning and collaboration of multiple *** complete real-time information sharing of multiple robots,we first build an acoustic communication system with excellent communication performance under low noise ratio ***,the task planning and collaboration control strategy adjust the SURs so that they maintain their positions in the desired formation when the formation *** SURs can move along desired trajectories in the expected *** control strategy of each SUR uses only its information and limited information of its neighboring ***,based on theoretical analysis and experiments,we evaluate the validity and reliability of the proposed *** comparison to the traditional leader–follower method,it is not necessary to designate a leader and its followers explicitly in our system;thus,important advantages,such as fault tolerance,are achieved.

关键词： Task planning Collaboration control Multiple spherical underwater robots(SUR) Shape keeping

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Innovative design and optimization of a two-dimensional deployable nine-grid planar antenna mechanism with a flat reflection surface

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Chinese Journal of Aeronautics 2023年第11期36卷 529-550页

作者： Bo CHEN Ze JIANG Xinlu WEI Luyao GUO Xin ZHOU Yundou XU Junjie QIAN Yongsheng ZHAO Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan UniversityQinhuangdao 066004China Key Laboratory of Advanced Forging&Stamping Technology and Science of Ministry of National Education Yanshan UniversityQinhuangdao 066004China Space Structure and Mechanism Technology Laboratory of China Aerospace Science and Technology Group Co.Ltd Shanghai 201109China Aerospace System Engineering Shanghai Shanghai 201109China

With the development of the aerospace industry,space missions are becoming more complicated and diversified,and there is a demand for antenna mechanisms with a larger physical *** this paper,a planar deployable mechanism is proposed,which can form a flat reflection surface with a small gap between *** this end,a novel large-scale two-dimensional deployable nine-grid planar antenna mechanism is ***,two antenna folding schemes and four supporting mechanism schemes are *** comparison analysis,the antenna configuration scheme with the best comprehensive performance is selected.A kinematic model of the deployable mechanism is established,and its kinematic characteristics are ***,the correctness of the kinematic model is verified by comparing the analytical and simulation results of the kinematic ***,a finite element model of the antenna is *** on the response surface method,the structural parameters of the support rods of the antenna are optimized,and a set of optimized solutions with lightweight and high fundamental frequency characteristics are ***,a prototype of the proposed nine-grid planar antenna is *** feasibility of the deployment principle and the rationality of the designed mechanism are verified by deployment experiments.

关键词： Design optimization Kinematics Planar antenna Structural design Two-dimensional expansion

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Ultra-low power MoS2 optoelectronic synapse with wavelength sensitivity for color target recognition

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science China(information sciences) 2025年第4期68卷 187-196页

作者： Bo WEI Yabo CHEN Xiaotong HAN Yan KANG Bujia LIANG Cheng LI Xiaokuo YANG Liang FANG Yuanxi PENG Institute for Quantum Information & State Key Laboratory of High Performance Computing College of ComputerNational University of Defense Technology Fundamentals Department Air Force Engineering University College of Advanced Interdisciplinary Studies National University of Defense Technology Institute of Quantum Information Science and Technology College of ScienceNational University of Defense Technology College of Computer National University of Defense Technology

Optoelectronic synapses that integrate visual perception and pre-processing hold significant potential for neuromorphic vision systems（NVSs）. However, due to a lack of wavelength sensitivity, existing NVS mainly focuses on gray-scale image processing, making it challenging to recognize color images. Additionally, the high power consumption of optoelectronic synapses, compared to the 10 fJ energy consumption of biological synapses, limits their broader application. To address these challenges, an energy-efficient NVS capable of color target recognition in a noisy environment was developed,utilizing a MoS2optoelectronic synapse with wavelength sensitivity. Benefiting from the distinct photon capture capabilities of 450, 535, and 650 nm light, the optoelectronic synapse exhibits wavelength-dependent synaptic plasticity, including excitatory postsynaptic current（EPSC）, paired-pulse facilitation（PPF）, and long-term plasticity（LTP）. These properties can effectively mimic the visual memory and color discrimination functions of the human vision system. Results demonstrate that the NVS, based on MoS2optoelectronic synapses, can eliminate the color noise at the sensor level, increasing color image recognition accuracy from 50% to 90%. Importantly, the optoelectronic synapse operates at a low voltage spike of0.0005 V, consuming only 0.075 fJ per spike, surpassing the energy efficiency of both existing optoelectronic and biological synapses. This ultra-low power, color-sensitive device eliminates the need for color filters and offers great promise for future deployment in filter-free NVS.

关键词： optoelectronic synapse neuromorphic vision system color recognition 2D materials image pre-processing

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Security of quantum key distribution with virtual mutually unbiased bases

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science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 13-21页

作者： Hong-Wei Li Chen-Peng Hao Zhi-Jiang Chen Li Gong Yi-Fei Lu Yang Wang Jia-Ji Li Chun-Mei Zhang Rong Wang Zhen-Qiang Yin Qing-Yu Cai Henan Key Laboratory of Quantum Information and Cryptography SSF IEUZhengzhou 450000China Institute of Quantum Information and Technology Nanjing University of Posts and TelecommunicationsNanjing 210003China Department of Physics University of Hong KongHong Kong 999077China Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China School of Information and Communication Engineering Hainan UniversityHaikou 570228China

In a perfect quantum key distribution(QKD)protocol,quantum states should be prepared and measured with mutually unbiased bases(MUBs).However,in a practical QKD system,quantum states are generally prepared and measured with imperfect MUBs using imperfect devices,possibly reducing the secret key rate and transmission *** analyze the security of a QKD system with imperfect MUBs,we propose virtual MUBs to characterize the quantum channel against collective attack,and analyze the corresponding secret key rate under imperfect state preparation and measurement *** generally,we apply the advantage distillation method for analyzing the security of QKD with imperfect MUBs,where the error tolerance and transmission distance can be sharply *** analysis method can be applied to benchmark and standardize a practical QKD system,elucidating the security analysis of different QKD protocols with imperfect devices.

关键词： quantum key distribution mutually unbiased bases advantage distillation

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A Fourth-Order Bandpass Filter with High Selectivity and Out-of-Band Suppression

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Progress In Electromagnetics Research C 2023年 134卷 237-247页

作者： Sun, Ming-Ming Xu, Yun-Sheng Zhang, Qiao Chen, Chang Zhou, Lingyun Key Laboratory of Electromagnetic Space Information of the Chinese Academy of Sciences Department of Electronic Engineering and Information Science University of Science and Technology of China Anhui Hefei230027 China

This paper presents a novel fourth-order bandpass filter with high selectivity and out-of-band suppression based on equivalent magnetic side wall cavities (MSWCs). By loading a via hole into an MSWC to produce a zero mode as a non-resonating node and using the dual MSWC modes TEM001 and TE100 as resonant modes, a modified doublet with two poles and two transmission zeros (TZs) can be formed. Three types of frequency response, either quasi-elliptic or asymmetric, can be obtained and designed flexibly. The TZs can be located on both sides of the passband or both on just one side. The mechanisms for generating the TZs are analyzed, and the adjustment of the TZ positions is discussed. The proposed four-pole quasi-elliptic filter with four TZs is a cascade of two such doublets with two different types of asymmetric response. It has been fabricated and measured to validate the design. Comparison is made with some previous work on substrate integrated waveguide filters. The developed filter is free from radiation and relatively compact among high order filters with multiple adjustable TZs based on cascaded cavities of the substrate integrated waveguide type. © 2023, Electromagnetics Academy. All rights reserved.

关键词： Substrate integrated waveguides

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Two-dimensional violet phosphorus as a broadband saturable absorber for mid-infrared photonics

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Optics Express 2025年第10期33卷 21328-21338页

作者： Li, Bo Pan, Han Pan, Zhongben Chu, Hongwei Li, Ying Zhao, Shengzhi Li, Dechun School of Information Science and Engineering Shandong Provincial Key Laboratory of Laser Technology and Application Key Laboratory of Laser and Infrared System of Ministry of Education Shandong University Qingdao266237 China Key Laboratory of Colloid and Interface Chemistry of Education Ministry School of Chemistry and Chemical Engineering Shandong University Jinan250100 China

Two-dimensional (2D) violet phosphorus (VP), a recently investigated 2D semiconductor material, is promising for advanced optoelectronic applications because of its distinct physical and chemical features. In this work, high-quality, few-layered, 2D VP nanosheets were prepared, and their nonlinear optical (NLO) absorption characteristics were examined in detail in the 2 and 3 µm bands. The calculated high nonlinear absorption coefficients, low saturation intensities, and high modulation depths of 2D VP nanosheets demonstrated their exceptional mid-infrared (MIR) saturable absorption properties and significant potential for MIR photonic applications. Thus, in the Tm: GdVO4 laser and Er: YAP laser, we employed 2D VP as a broadband saturable absorber (SA), and obtained stable Q-switched pulse outputs with pulse durations of 522.6 ns at 1.9 µm and 195 ns at 2.8 µm, respectively. In particular, the pulse width obtained at 3 µm based on 2D VP-SA is much narrower compared to that obtained for most other 2D materials SAs. These results demonstrate that 2D VP can be a potential candidate for broadband MIR SA. © 2025 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement.

关键词： Nanosheets

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