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2022 IEEE International Conference on Unmanned Systems, ICUS 2022

作者： He, Yuxin Zhuang, Yaqiang Zhuang, Xuebin Lin, Zijian School of System Science and Engineering Sun Yat-sen University Guangzhou China School of Integrated Circuits and Electronics Beijing Institute of Technology Beijing Key Laboratory of Millimeter Wave and Terahertz Technology Beijing China Science and Technology On Complex Aviation Systems Simulation Laboratory Beijing China

ISBN: (数字)9781665484565

ISBN: (纸本)9781665484565

By broadcasting false Global Navigation Satellite System (GNSS) signals, spoofing attacks will induce false position and time fixes within the victim receiver. In this article, we propose a Sparse Decomposition (SD)-based spoofing detection algorithm in the acquisition process, which can be applied in a single-antenna receiver. In the first step, we map the Fast Fourier transform (FFT)-based acquisition result in a two-dimensional matrix, which is a distorted autocorrelation function when the receiver is under spoof attack. In the second step, the distorted function is decomposed into two main autocorrelation function components of different code phases. The corresponding elements of the result vector of the SD are the code-phase values of the spoofed and the authentic signals. Numerical simulation results show that the proposed method can not only outcome spoofing detection result, but provide reliable estimations of the code phase delay of the spoof attack. © 2022 IEEE.

关键词： Fast Fourier transforms

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Shear induced deformation twinning evolution in thermoelectric InSb

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npj Computational Materials 2021年第1期7卷 1008-1016页

作者： Zhongtao Lu Ben Huang Guodong Li Xiaolian Zhang Qi An Bo Duan Pengcheng Zhai Qingjie Zhang William A.Goddard III Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics School of ScienceWuhan University of TechnologyWuhanPR China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhanPR China Department of Chemical and Materials Engineering University of Nevada RenoRenoNVUSA Materials and Process Simulation Center California Institute of TechnologyPasadenaCAUSA

Twin boundary(TB)engineering has been widely applied to enhance the strength and plasticity of metals and alloys,but is rarely adopted in thermoelectric(TE)*** previous first-principles results showed that nanotwins can strengthen TE Indium Antimony(InSb)through In–Sb covalent bond rearrangement at the ***,we further show that shear-induced deformation twinning enhances plasticity of *** demonstrate this by employing large-scale molecular dynamics(MD)to follow the shear stress response of flawless single-crystal InSb along various slip *** observed that the maximum shear strain for the (111)[112] slip system can be up to 0.85 due to shear-induced deformation *** attribute this deformation twinning to the“catching bond”involving breaking and re-formation of In–Sb bond in *** finding opens up a strategy to increase the plasticity of TE InSb by deformation twinning,which is expected to be implemented in other isotypicⅢ–V semiconductors with zinc blende structure.

关键词： deformation plasticity Shear

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Accelerating ab initio real-space electronic structure calculations for low-dimensional materials using an atom-sphere grid truncation method

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Physical Review B 2024年第15期110卷 155157页

作者： Lantian Xue Qiang Xu Cheng Ma Wenhui Mi Yanchao Wang Yu Xie Yanming Ma Key Laboratory of Material Simulation Methods & Software of Ministry of Education College of Physics State Key Lab of Superhard Materials College of Physics International Center of Future Science Key Laboratory of Physics and Technology for Advanced Batteries of Ministry of Education College of Physics

In recent decades, the real-space finite-difference implementations of Kohn–Sham density functional theory have exhibited substantial improvements in computational efficiency for large-scale systems. However, the substantial memory consumption arising from the numerous grid points has begun to limit the widespread adoption of this method. In this study, a general method is presented—applicable to both periodic and Dirichlet boundary conditions—to reduce the number of real-space grids. This approach introduces a truncation of the real-space grids based on atomic positions, which reduces memory requirements and enables a more efficient real-space scheme tailored for simulating low-dimensional and porous materials with uneven spatial distributions. By testing the method on zero-dimensional clusters, one-dimensional tubes, two-dimensional clusters adsorbed on graphene, and three-dimensional metal-organic framework materials, a 30–73% reduction in grid points and a 36–71% reduction in computational time per step are observed for simulations with a 2 meV/atom energy difference.

关键词： Electronic structure Density functional theory development First-principles calculations Numerical techniques

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Influence of Nanoceramic Particle Size on the Wear Resistance of Micro-Arc Oxidation Coatings for 2a12 Aluminum Alloy

SSRN

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SSRN 2024年

作者： Li, Wen Cheng, Ming Zhang, Xiaochen Wei, Guoke Aviation Key Laboratory of Science and Technology on Advanced Surface Engineering AVIC Manufacturing Technology Institute Beijing100024 China Science and Technology on Power Beam Processes Laboratory AVIC Manufacturing Technology Institute Beijing100024 China

The 2A12 aluminum alloy, renowned for its exceptional mechanical properties, faces significant limitations in applications involving abrasive environments or frequent contact with other surfaces due to its inadequate wear resistance. This shortcoming substantially reduces the service life of components and escalate maintenance costs, highlighting the urgent need for advanced surface modification techniques. This study meticulously investigates the influence of nanoceramic particle size on the wear resistance of micro-arc oxidation (MAO) coatings, a surface modification method known for forming dense, adherent ceramic layers on aluminum alloys. The systematic experimentation revealed that the incorporation of 150 nm α-Al2O3 nanoparticles into the MAO matrix achieves an optimal dispersion, leading to a substantial enhancement in wear resistance. The sample with 5g/L of 150 nm α-Al2O3 nanoparticles doping in the MAO electrolyte demonstrated the lowest mass loss, underscoring its superior wear resistance. The improved microstructure, enriched with hard ceramic phases such as α-Al2O3 and mullite, plays a pivotal role in withstanding wear. Moreover, this study identified that an optimal balance of surface roughness and coating thickness is essential for achieving enhanced wear resistance. The findings of this research provide a compelling strategy for the design of wear-resistant coatings tailored for high-performance applications across aerospace, automotive, and general engineering industries. By optimizing the particle size and concentration in MAO coatings, this study paves the way for the development of durable materials capable of thriving in demanding environments, thereby extending the service life and reducing maintenance requirements of components. © 2024, The Authors. All rights reserved.

关键词： Wear resistance

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The staggered-layer induced elasticity strengthening mechanism in flexible Bi2Te3

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Matter 2025年

作者： Huang, Xiege Wu, Luoqi Hu, Mingyuan Feng, Xiaobin Zhai, Pengcheng Li, Wenjuan Duan, Bo He, Jiaqing Li, Guodong Zhang, Qingjie Goddard, William A. Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics School of Physics and Mechanics Wuhan University of Technology Wuhan430070 China Guangdong Provincial Key Laboratory of Advanced Thermoelectric Materials and Device Physics Shenzhen Key Laboratory of Thermoelectric Materials and Department of Physics Southern University of Science and Technology Shenzhen518055 China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan430070 China Materials and Process Simulation Center California Institute of Technology PasadenaCA91125 United States

Wearable flexible devices require the development of thermoelectric (TE) materials with high strength, excellent elastic bendability, and superior ductility. Here we report a staggered-layer strategy that overcomes the strength-flexibility dilemma. Our findings indicate that the newly formed strong Bi–Bi covalent bond between the staggered layer leads to an average 40% increase in the bond energy of the van der Waals Te–Te bond. A large Poisson's ratio leads to a high maximum linear elastic strain (ΕEmax), enhancing shear strength by 83.3%, which is consistent with a 92.2% increase in micro-pillar compressive strength. The narrow stiffness gap and bond energy gap facilitate the coordinated deformation that maintains sustained linear elasticity during compression. Moreover, the low BFCs of the Te–Te and Te–Bi bonds (0.72 eV/Å2 and 3.85 eV/Å2) contribute to the experimentally observed bending flexibility. This staggered-layer-induced elasticity strengthening mechanism offers a promising strategy for the rational design of highly reliable wearable TE devices. © 2025 Elsevier Inc.

关键词： Compressive strength

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Simultaneously achieving high energy density and responsivity in submicron BaTiO_(3) film capacitors integrated on Si

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Journal of advanced Ceramics 2024年第2期13卷 198-206页

作者： Jun Ouyang Yinxiu Xue Chuanqi Song Meiling Yuan Kun Wang Yuyao Zhao Hongbo Cheng Hanfei Zhu Chao Liu Institute of Advanced Energy Materials and Chemistry School of Chemistry and Chemical EngineeringQilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Key Laboratory of Key Film Materials&Application for Equipment School of Material Sciences and EngineeringXiangtan UniversityXiangtan 411105China School of Materials Science and Engineering Shandong UniversityJinan 250061China Academic Affairs Office Civil Aviation University of ChinaTianjin 300300China China Tobacco Shandong Industrial Co. Ltd.Jinan 250014China

In the research field of energy storage dielectrics,the“responsivity”parameter,defined as the recyclable/recoverable energy density per unit electric field,has become critically important for a comprehensive evaluation of the energy storage capability of a *** this work,high recyclable energy density and responsivity,i.e.,W_(rec)=161.1 J·cm^(-3) and ξ=373.8 J·(kV·m^(2))^(-1),have been simultaneously achieved in a prototype perovskite dielectric,BaTiO_(3),which is integrated on Si at 500℃ in the form of a submicron thick *** ferroelectric film features a multi-scale polar structure consisting of ferroelectric grains with different orientations and inner-grain ferroelastic domains.A LaNiO_(3) buffer layer is used to induce a{001}textured,columnar nanograin microstructure,while an elevated deposition temperature promotes lateral growth of the nanograins(in-plane diameter increases from~10-20 nm at lower temperatures to~30 nm).These preferably oriented and periodically regulated nanograins have resulted in a small remnant polarization and a delayed polarization saturation in the film’s P-E behavior,leading to a high recyclable energy ***,an improved polarizability/dielectric constant of the BaTiO_(3) film has produced a much larger maximum polarization than those deposited at lower temperatures at the same electric field,leading to a record-breaking responsivity for this simple perovskite.

关键词： energy storage energy density responsivity BaTiO_(3) dielectric capacitor Si

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Compact generation scheme of path–frequency hyperentangled photons using 2D periodical nonlinear photonic crystal

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Chinese Physics B 2023年第12期32卷 256-262页

作者：陈洋河季波李念芹姜震李维李昱东冯梁森武腾飞何广强 SJTU Pinghu Institute of Intelligent Optoelectronics Department of Electronic EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronic EngineeringShanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Metrology and Calibration Laboratory Changcheng Institute of Metrology&MeasurementAviation Industry Corporation of ChinaBeijing 100095China

Hyperentanglement is a promising resource for achieving high capacity quantum ***,we propose a compact scheme for the generation of path-frequency hyperentangled photon pairs via spontaneous parametric down-conversion(SPDC)processes,where six different paths and two different frequencies are covered.A two-dimensional periodicalχ^((2))nonlinear photonic crystal(NPC)is designed to satisfy type-Ⅰquasi-phase-matching conditions in the plane perpendicular to the incident pump beam,and a perfect phase match is achieved along the pump beam's direction to ensure high conversion efficiency,with theoretically estimated photon flux up to 2.068×10^(5) pairs·s^(-1)·mm^(-2).We theoretically calculate the joint-spectral amplitude(JSA)of the generated photon pair and perform Schmidt decomposition on it,where the resulting entropy S of entanglement and effective Schmidt rank K reach 3.2789 and 6.4675,*** hyperentangled photon source scheme could provide new avenues for high-dimensional quantum communication and high-speed quantum information processing.

关键词： hyperentanglement nonlinear photonic crystal quasi-phase-matching

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The missing base molecules in atmospheric acid-base nucleation

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National science Review 2022年第10期9卷 196-208页

作者： Runlong Cai Rujing Yin Chao Yan Dongsen Yang Chenjuan Deng Lubna Dada Juha Kangasluoma Jenni Kontkanen Roope Halonen Yan Ma Xiuhui Zhang Pauli Paasonen Tuukka Pet?j? Veli-Matti Kerminen Yongchun Liu Federico Bianchi Jun Zheng Lin Wang Jiming Hao James N.Smith Neil M. Donahue Markku Kulmala Douglas R.Worsnop Jingkun Jiang State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Institute for Atmospheric and Earth System Research/Physics Faculty of Science University of Helsinki Aerosol and Haze Laboratory Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing University of Information Science and Technology Laboratory of Atmospheric Chemistry Paul Scherrer Institute Center for Joint Quantum Studies and Department of Physics School of Science Tianjin University Key Laboratory of Cluster Science Ministry of Education of China School of Chemistry and Chemical Engineering Beijing Institute of Technology Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3) Department of Environmental Science and Engineering Fudan University Chemistry Department University of California Center for Atmospheric Particle Studies Carnegie Mellon University Department of Chemistry Carnegie Mellon University Aerodyne Research Inc.

Transformation of low-volatility gaseous precursors to new particles affects aerosol number concentration,cloud formation and hence the *** clustering of acid and base molecules is a major mechanism driving fast nucleation and initial growth of new particles in the ***,the acid-base cluster composition,measured using state-of-the-art mass spectrometers,cannot explain the measured high formation rate of new *** we present strong evidence for the existence of base molecules such as amines in the smallest atmospheric sulfuric acid clusters prior to their detection by mass *** demonstrate that forming（H2SO4）1（amine）1is the rate-limiting step in atmospheric H2SO4-amine nucleation and the uptake of（H2SO4）1（amine）1is a major pathway for the initial growth of *** proposed mechanism is very consistent with measured new particle formation in urban Beijing,in which dimethylamine is the key base for H2SO4nucleation while other bases such as ammonia may contribute to the growth of larger *** findings further underline the fact that strong amines,even at low concentrations and when undetected in the smallest clusters,can be crucial to particle formation in the planetary boundary layer.

关键词： new particle formation acid-base nucleation aerosol polluted urban environment

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Research on Modular Inverter Control technology of Dual Three-Phase Permanent Magnet Synchronous Motor

Research on Modular Inverter Control Technology of Dual Thre...

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IEEE International Conference on Power and Power and Renewable Energy (ICPRE)

作者： Changfang Wei Yiming Song Jin Wang Libing Zhou State Key Laboratory of Advanced Electromagnetic Technology Huazhong University of Science and Technology Wuhan China AECC Hunan Aviation Powerplant Research Institute Zhuzhou China

ISBN: (数字)9798350377460

ISBN: (纸本)9798350377477

Using medium-voltage DC transmission instead of traditional three-phase AC transmission can significantly reduce cable losses. However, high DC bus voltages pose challenges for voltage equalization across inverter modules. This paper proposes a topology for a modular dual three-phase permanent magnet synchronous motor (PMSM) inverter, and studies its dual closed-loop vector control and modular inverter voltage equalization control strategies. By using a series connection of inverters and three-phase decoupled PWM technology for individual control of inverter modules, a modular inverter series bus voltage equalization control strategy is established. Compared to parallel modular inverter, it can further reduce voltage fluctuations and enhance the dynamic performance of the motor. simulation has verified the performance of the motor operation based on this control strategy, demonstrating that this method can achieve effective voltage equalization.

关键词： Renewable energy sources Voltage fluctuations Fluctuations Pulse width modulation Permanent magnet motors Inverters Stability analysis Topology Voltage control Underwater vehicles

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Three-dimensional temperature prediction in cylindrical turning with large-chamfer insert based on a modified slip-line field approach

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Chinese Journal of Aeronautics 2021年第10期34卷 265-281页

作者： Cheng HU Kejia ZHUANG Yuanwei TANG Jian WENG Xiaoming ZHANG Han DING Hubei Digital Manufacturing Key Laboratory School of Mechanical and Electronic EngineeringWuhan University of TechnologyWuhan 430070China Institute of Advanced Materials and Manufacturing Technology Wuhan University of TechnologyWuhan 430070China AECC Guizhou Liyang Aviation Power CO.LTD Guiyang 550000China State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

Chamfered inserts have found broader applications in metal cutting process especially in high-performance machining of hard-to-cut materials for their excellent edge resistance and cutting ***,excessive heat generation and resulting high cutting temperature eventually cause severe tool wear and poor surface integrity,which simultaneously limits the optimal selection of machining *** the present study,an analytical thermal–mechanical model is proposed for the prediction of the three-dimensional(3-D)temperature field in cylindrical turning with chamfered round insert based on a modified slip-line field ***,an innovative discretization method is introduced in a general 3-D coordinate system to provide a comprehensive demonstration of the irregular cutting geometry and heat generation ***,a plasticity-theory-based slip-line field model is developed and employed to determine the intensities and geometries of every elementary heat sources in Primary Deformation Zones(PDZ),Secondary Deformation Zones(SDZ)and Dead Metal Zones(DMZ).At last,a 3-D analytical model is suggested to calculate the temperature increases caused by the entire heat sources and associated *** maximum cutting temperature region predicted is found existing upon the chip-tool contact area rather than the tool ***,the rationalities of cutting parameters employed are analyzed along with theoretical material removal rates and ensuing maximum cutting *** results indicate that the cutting conditions with large depth of cut and high cutting speed are more desirable than those with high feed *** proposed models are respectively verified through a series of 3-D Finite Element(FE)simulations and dry cutting experiments of Inconel 718 with chamfered round *** agreement has been reached between the predictions and simulations as well as the measurements,which confirms the correctness and effectiveness of the presented analy

关键词： Analytical model Chamfered round insert Dead metal zone Prediction of temperature Slip-line field

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