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IEEE Transactions on Green Communications and Networking 2025年

作者： Hu, Cong Chen, Yuanxiang Du, Chaoyi Bai, Hao Wang, Shuo Yu, Jianguo Lu, Fan Fan, Zhanchun Beijing University of Posts and Telecommunications School of Electronic Engineering Beijing100876 China Xidian University State Key Laboratory of Integrated Services Networks Xi'an710071 China Beijing Institute of Spacecraft System Engineering Beijing100094 China

Full-duplex (FD) systems enable users to simultaneously transmit and receive information on the same frequency, theoretically enhancing spectrum efficiency. However, the inherent openness and broadcasting nature of wireless communication pose significant security risks, especially in the presence of eavesdroppers. To enhance the reliability of FD relay systems, we derive the secrecy capacity of the systems and propose a novel approach that integrates relay selection and power allocation utilizing deep reinforcement learning (DRL). Specifically, our method employs deep Q network (DQN) and proximal policy optimization (PPO) algorithms to jointly explore the optimal relay selection and power allocation strategies. simulation results indicate that the developed approach enhances the average secrecy capacity by at least 30% compared to benchmark methods. Additionally, we assessed the performance of various methods under diverse conditions, demonstrating the effectiveness and adaptability of the proposed approach. © 2024 IEEE.

关键词： Deep reinforcement learning

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Domain knowledge discovery from abstracts of scientific literature on Nickel-based single crystal superalloys

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Science China(Technological Sciences) 2023年第6期66卷 1815-1830页

作者： LIU Yue DING Lin YANG ZhengWei GE XianYuan LIU DaHui LIU Wei YU Tao AVDEEV Maxim SHI SiQi School of Computer Engineering and Science Shanghai UniversityShanghai 200444China Shanghai Engineering Research Center of Intelligent Computing System Shanghai 200444China State Key Laboratory of Advanced Special Steel&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Materials Genome Institute Shanghai UniversityShanghai 200444China Institute of Functional Materials Central Iron&Steel Research InstituteBeijing 100081China Australian Nuclear Science and Technology Organisation Locked Bag 2001Kirrawee DC NSW 2232Australia School of Chemistry The University of SydneySydney 2006Australia Zhejiang Laboratory Hangzhou 311100China

Despite the huge accumulation of scientific literature,it is inefficient and laborious to manually search it for useful information to investigate structure-activity ***,we propose an efficient text-mining framework for the discovery of credible and valuable domain knowledge from abstracts of scientific literature focusing on Nickel-based single crystal ***,the credibility of abstracts is quantified in terms of source timeliness,publication authority and author’s academic ***,eight entity types and domain dictionaries describing Nickel-based single crystal superalloys are predefined to realize the named entity recognition from the abstracts,achieving an accuracy of 85.10%.Thirdly,by formulating 12 naming rules for the alloy brands derived from the recognized entities,we extract the target entities and refine them as domain knowledge through the credibility *** this,we also map out the academic cooperative“Author-Literature-institute”network,characterize the generations of Nickel-based single crystal superalloys,as well as obtain the fractions of the most important chemical elements in *** extracted rich and diverse knowledge of Nickel-based single crystal superalloys provides important insights toward understanding the structure-activity relationships for Nickel-based single crystal superalloys and is expected to accelerate the design and discovery of novel superalloys.

关键词： Nickel-based single crystal superalloys text mining named entity recognition credibility analysis domain knowledge

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MECHANICAL CHARACTERISTICS ANALYSIS OF CORNER TENSIONED RECTANGULAR THIN MEMBRANES 1

MECHANICAL CHARACTERISTICS ANALYSIS OF CORNER TENSIONED RECT...

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1st International Conference on Mechanical system Dynamics, ICMSD 2022

作者： Li, Bingyan Peng, Tao Lin, Qiuhong Wang, Xiaoyu Cong, Qiang Tian, Xinqi Liu, Rongqiang Beijing Institute of Spacecraft Engineering Beijing100094 China State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin150001 China College of Mechanical and Electrical Engineering Harbin Engineering University Harbin150001 China

ISBN: (数字)9781839537837

ISBN: (纸本)9781839537837

This paper presents the calculation of the stress distribution of corner tensioned rectangular thin membrane based on the stress superposition method (SSM). By comparing with the results of finite element simulation, the theoretical results of stress distribution of tensioned membrane structure are verified. Based on SSM and free vibration calculation theory, the effects of tension boundary parameters on membrane stress distribution and models are investigated. The influence of corner tension on the mechanical characteristics is analyzed for the corner tensioned rectangular membranes with different aspect ratios. The formula for each order's fundamental frequency ratio of atmospheric to spatial environment is proposed. Conducting the dynamics experiment of a rectangular tensioned membrane, the theoretical analysis is verified by the experimental modal results. © 2022 IET Conference Proceedings. All rights reserved.

关键词： Stress concentration

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Electromagnetic scattering characterization of a layered rough soil ground

Electromagnetic scattering characterization of a layered rou...

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2024 International Conference on Power system engineering and Smart Grid, PSESG 2024

作者： Zhang, Jiangong Yu, Pengcheng Gan, Zheyuan Chen, Yajie Cao, Xiaoyu Zhao, Zhibin Jiao, Chaoqun State Key Laboratory of PowerGrid Environmental Protection China Electric Power Research Institute Wuhan Branch Hubei Wuhan43000 China Jinhua Power Supply Company State Grid Zhejiang Electric Power Company Zhejiang Jinhua321000 China School of Electrical Engineering Beijing Jiaotong University Beijing100044 China State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University Beijing102206 China

As the density of additional ultra-high voltage alternating current and direct current transmission lines in China increases, so does the passive interference from transmission lines to various types of equipment. At present, the objective of previous studies is to examine the impact of passive interference on the performance of transmission lines, ignoring the impact of rough soil ground on the passive interference of transmission line. Put it another way, the earth as a pure conductor processing, the use of this simplified processing method of the results obtained from the measured value is often a large deviation. For this reason, this paper considers the added transmission line erected in the rough soil ground environment. A more realistic passive interference model for ultra-high voltage transmission lines developed. We are looking at how electromagnetic waves behave when they are transmitted through different types of rough soil. To do this, we have created a model of layered rough soil using the Monte Carlo method. Then, the scattering coefficients of layered rough soil ground at two stations are calculated by going to use the method of moments. In the end, the effects of roughness change and distance change of layered rough soil ground on the scattering coefficients are investigated, and a model of layered rough soil ground is established on the basis of single-layered rough ground to take a look at how electromagnetic waves behave when they hit layered, uneven soil. © 2024 institute of Physics Publishing. All rights reserved.

关键词： Soil mechanics

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Contributions of moisture sources to precipitation in the major drainage basins in the Tibetan Plateau

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Science China Earth Sciences 2022年第6期65卷 1088-1103页

作者： Ying LI Fengge SU Qiuhong TANG Hongkai GAO Denghua YAN Hui PENG Shangbin XIAO Engineering Research Center of Eco-environment in Three Gorges Reservoir Region Yichang 443002China College of Hydraulic and Environmental Engineering China Three Gorges UniversityYichang 443002China State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of Sciences(CAS)Beijing 100101China University of Chinese Academy of Sciences Beijing 100101China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China Key Laboratory of Water Cycle and Related Land Surface Process Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Geographic Information Science(Ministry of Education of China) East China Normal UniversityShanghai 200241China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin Water Resources DepartmentChina Institute of Water Resources and Hydropower ResearchBeijing 100038China

Tracking and quantifying the moisture sources of precipitation in different drainage basins in the Tibetan Plateau(TP)help to reveal basin-scale hydrological cycle characteristics under the interactions between the westerlies and Indian summer monsoon(ISM) systems and to improve our understanding on the mechanisms of water resource changes in the ‘Asian Water Tower' under climate changes. Based on a Eulerian moisture tracking model(WAM-2) and three atmospheric reanalysis products(ERA-I, MERRA-2, and JRA-55), the contributions of moisture sources to the precipitation in six major sub-basins in the TP were tracked during an approximately 35-year period(1979/1980–2015). The results showed that in the upper Indus(UI),upper Tarim River(UT), and Qaidam Basin(QB), the moisture sources mainly extended westward along the mid-latitude westerlies to the western part of the Eurasian continent. In contrast, in the Yarlung Zangbo River Basin(YB), inner TP(ITP), and the source area of three eastern rivers(TER, including the Nujiang River, Lancang River, and Yangtze River), the moisture sources extended both westward and southward, but mainly southward along the ISM. In winter and spring, all of the sub-basins were dominated by western moisture sources. In summer, the western sources migrated northward with the zonal movement of the westerlies, and simultaneously the southern sources of the YB, ITP, and TER expanded largely toward the Indian Ocean along the ISM. In autumn, the moisture sources of the UI, UT, and QB shrank to the western sources, and the moisture sources of the YB, ITP, and TER shrank to the central-southern TP and the Indian subcontinent. By quantifying the moisture contributions from multiple sources, we found that the terrestrial moisture dominated in all of the sub-basins, particularly in the UT and QB(62–73%). The oceanic contributions were relatively high in the UI(38–42%) and YB(38–41%). In winter, evaporation from the large western water bodies(such as the M

关键词： Tibetan Plateau Precipitation Moisture sources Westerlies Indian summer monsoon Local recycling

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Dynamic state Estimation for Integrated Electricity-gas systems Based on Kalman Filter

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CSEE Journal of Power and Energy systems 2022年第1期8卷 293-303页

作者： Yanbo Chen Yuan Yao Yuzhang Lin Xiaonan Yang State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources School of Electrical&Electronic EngineeringNorth China Electric Power University102206 BeijingChina Qinghai Key Laboratory of Efficient Utilization of Clean Energy Tus-Institute for Renewable EnergyQinghai UniversityXining 810016China School of Engineering Xining UniversityXining 810016China School of Electrical&Electronic Engineering North China Electric Power University102206 BeijingChina Department of Electrical and Computer Engineering University of MassachusettsLowellMA 01852USA State Key Laboratory of Power Grid Safety and Energy Conservation China Electric Power Research Institute100192 BeijingChina

In recent years, integrated electricity-gas systems(IEGSs) have attracted widespread attention. The unifiedscheduling and control of the IEGS depends on high-precisionoperating data. To this end, it is necessary to establish anappropriate state estimation (SE) model for IEGS to filter theraw measured data. Considering that power systems and naturalgas systems have different time scales and sampling periods, thispaper proposes a dynamic state estimation (DSE) method basedon a Kalman filter that can consider the dynamic characteristicsof natural gas pipelines. First, the standardized state transitionequations for the gas system are developed by applying the finitedifference method to the partial differential equations (PDEs) ofthe gas system;then the DSE model for IEGS is formulatedbased on a Kalman filter;also, the measurements from theelectricity system and the gas system with different samplingperiods are fused to ensure the observability of DSE by using theinterpolation method. The IEEE 39-bus electricity system and the18-nodes Belgium gas system are integrated as the test *** results verify the proposed method’s accuracy andcalculation efficiency.

关键词： Dynamic state estimation integrated electricitygas system Kalman filter two time-scale measurements transition state equation

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Energy-saving Superconducting Magnetic Energy Storage(SMES)Based Interline DC Dynamic Voltage Restorer

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CSEE Journal of Power and Energy systems 2022年第1期8卷 238-248页

作者： Xiaoyuan Chen Qi Xie Xingming Bian Boyang Shen Institute of Applied Superconductivity and Energy Efficiency School of EngineeringSichuan Normal UniversityChengdu 610101China State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China Electrical Engineering Division Department of EngineeringUniversity of CambridgeCambridge CB30FAUnited Kingdom

The fast-response feature from a superconducting magnetic energy storage(SMES)device is favored for suppressing instantaneous voltage and power fluctuations,but the SMES coil is much more expensive than a conventional battery energy storage *** order to improve the energy utilization rate and reduce the energy storage cost under multiple-line power distribution conditions,this paper investigates a new interline DC dynamic voltage restorer(IDC-DVR)scheme with one SMES coil shared among multiple compensating *** this new concept,an improved current-voltage(I/V)chopper assembly,which has a series of input/output power ports,is introduced to connect the single SMES coil with multiple power lines,and thereby satisfy the independent energy exchange requirements of any line to be ***,if two or more power lines have simultaneous compensating demands,the SMES coil can be selectively controlled to compensate the preferable line according to the priority order of the *** feasibility of the proposed scheme is technically verified to maintain the transient voltage stability in multiple-line voltage swell and sag cases caused by either output voltage fluctuations from external power sources or power demand fluctuations from local sensitive *** simulation results provide a technical basis to develop a cost-effective SMES-based IDC-DVR for use in various DC distribution networks.

关键词： DC distribution dynamic voltage restorer(DVR) interline DC dynamic voltage restorer superconducting magnetic energy storage(SMES) transient voltage stability

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A Closed-Loop Current Balancing Control Strategy in Multilevel Current Source Converter 4

A Closed-Loop Current Balancing Control Strategy in Multilev...

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4th International Conference on Energy, Power and Electrical engineering, EPEE 2024

作者： Zhou, Tianji Lou, Yantao Sun, Xiaoping He, An Yang, Liu Wu, Yue Tsinghua University Department of Electrical Engineering Beijing China Xi'an Xidian Power System Co. Ltd. Department of Dc Research Xi'an China Electric Power Research Institute China Southern Power Grid State Key Laboratory of Hvdc Guangzhou China

ISBN: (纸本)9798331518066

The rapid growth of clean energy has increased the demand for rectifier power supplies in hydrogen production, particularly in the megawatts (MW) and kiloamperes (kA) range. The Multilevel Current Source Converter (MCSC), a modular and multilevel topology with high power quality, is suitable for high-current applications but faces challenges, notably current balancing among submodules (SMs). This paper analyzes the causes of current imbalance and proposes a closed-loop control strategy using module current feedback and modulation index adjustment to maintain balanced current across the 2 N DC ports in a MCSC formed by N SMs. Finally, simulation results in MATLAB/Simulink confirm the effectiveness of the proposed current balancing control strategy. © 2024 IEEE.

关键词： Closed loop control systems

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Photochemical Reduction of Particle Bound Mercury in Atmospheric Aerosol Water

ACS ES&T Air

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ACS ES&T Air 2024年第3期1卷 150-161页

作者： Deming Han Qingru Wu Shuxiao Wang Changlei Xie Jianbo Shi Wang Zheng Jiubin Chen Yi Tang Daiwei Ouyang Boyang Feng Minneng Wen Lei Duan Jiming Hao State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Tsinghua University 100084 Beijing China School of Environment Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences 310000 Hangzhou China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex 100084 Beijing China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences 100085 Beijing China Institute of Surface-Earth System Science School of Earth System Science Tianjin University 300072 Tianjin China

Particle bound mercury (PBM) deposition on the Earth’s surface threatens biota and humans. The photoreduction of PBM competes with deposition and thereby modifies global mercury cycling; yet, its pathway and mechanism remain poorly understood. Herein, we reveal the photoreduction process of PBM by comprehensively using field observation, mercury stable isotope analysis, and controlled experiment. We found the Δ199Hg values in wet haze episodes (0.34‰ ± 0.30‰) were significantly higher than those in clean periods (0.14‰ ± 0.19‰), majorly attributed to the elevated aerosol water content (AWC), which shifts the aerosol phase from the solid state to the liquid state, promoting soluble HgCl2and HgBr2photoreduction reactions. The carboxyl functional groups of water-soluble organic carbon (WSOC) were further identified as the crucial compounds that induce PBM photoreduction, whose reaction rates were ∼2 times higher than those of phenol and ketone ligands and 3–6 times higher than those observed in other atmospheric aqueous phases. Considering the ubiquitously distributed carboxyl ligands and significant positive Δ199Hg signals in the atmospheric aqueous phases, the PBM photoreduction mediated by carboxyl ligands is highlighted to significantly influence global mercury transformations, regional depositions, and isotopic compositions of atmospheric mercury pools.

关键词： Aerosols Cations Ligands Mercury Redox reactions

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A Multilevel Current Source Converter with 19kA Output Capacity for Large-Scale Hydrogen Electrolyzer

A Multilevel Current Source Converter with 19kA Output Capac...

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2024 IEEE Energy Conversion Congress and Exposition, ECCE 2024

作者： Zhou, Tianji Zhao, Biao Yantao, Lou Xiaoping, Sun He, An Yang, Liu Wu, Yue Tang, Xueteng Tsinghua University Department of Electrical Engineering Beijing China Xi'an Xidian Power System Co. Ltd. Department of Dc Research Xi'an China China Southern Power Grid State Key Laboratory of Hvdc Electric Power Research Institute Guangzhou China

ISBN: (纸本)9798350376067

Multilevel current source converter (MCSC) is a modular topology suitable for buck-type continuously adjustable high output current rectifier application, realizing high controllability, high scalability, high reliability and low cost, which is suitable for large-scale hydrogen electrolyzer power supply. This paper presents the topology of IGBT-based MCSC and highlights its superiority over the existing electrolyzer power supply topologies. Design considerations are outlined to achieve low distortion AC current, low ripple DC current and a compact design of submodule (SM) is also introduced. The experiment scheme, realizing rated output and full-power operation, is presented. Additionally, a 19kA/6.65MW hydrogen electrolyzer power supply prototype based on MCSC is demonstrated to validate the performance, supported by experiment waveforms and results. © 2024 IEEE.

关键词： Topology

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