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5th IEEE Information Technology, Networking, Electronic and Automation Control Conference, ITNEC 2021

作者： Han, Chi Xiong, Wei Xiong, Minghui Liu, Zhen Liu, Wenwen Yu, Xiaolan Jian, Ping Space Engineering University Aerospace Information Institute Beijing China Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing China

ISBN: (纸本)9781665415989

Considering the complexity of effectiveness evaluation index of reconnaissance satellite system (RSS), the cloud model theory and AHP method are combined. A fuzzy evaluation method of combat effectiveness based on cloud model is proposed. A multi-layer evaluation index system is constructed through the AHP method, and the weight of each level index is calculated. Combining the multi-dimensional cloud model with the AHP method, a quantitative fuzzy evaluation method for qualitative indicators and quantitative data is designed, and the qualitative evaluation results are obtained. The experimental results show that the proposed evaluation method can effectively realize the fuzzy quantitative evaluation under the complex evaluation index system with good performance in terms of calculation accuracy and fuzziness. © 2021 IEEE.

关键词： Analytic hierarchy process

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Environment-friendly Insulating Gases for HVDC Gas-insulated Transmission Lines

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CSEE Journal of Power and Energy systems 2021年第3期7卷 510-529页

作者： Geng Chen Youping Tu Cong Wang Jue Wang Zhikang Yuan Guoming Ma Jian Wang Bo Qi Chuanyang Li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources and the Beijing Key Laboratory of High Voltage and EMC North China Electric Power UniversityBeijing 102206China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China Department of Electrical Engineering Tsinghua UniversityBeijing 100084China

Environment-friendly gas insulating mediums adapted to a DC gas-insulated transmission line(GIL)electric field condition is the key to the next generation of Environment-friendly HVDC *** this paper,we review the literature on sulfur hexafluoride(SF6)alternatives including the scientific understanding,control,and implementation of gas-solid systems in this type of power ***,the structure-activity relationship between the molecular structure and physico-chemical properties of Environment-friendly insulating gases is ***,the search and prediction of important physicochemical properties of gases are ***,in view of the potential of environmental friendly insulating gases,the swarm parameters of gas discharge and breakdown properties in a quasi-uniform field,inhomogeneous field,and at the gas-solid interface,that need to be taken into account with industrialized DC GILs are *** latest research progress on insulation characteristics,especially the polarity effect in DC gas-solid insulation systems,the sensitivity to the electrode surface state,and the non-uniformity of the electric field,and the influence of metal particles and their variation with air pressure,is *** addition,the heat transfer characteristics of insulating gases,related to DC GIL transmission with a large current-carrying capacity and the influence of alternative gases on the heat transfer characteristics are ***,aiming at solving the contradiction of low environmental impact,high dielectric strength and low liquefaction temperatures in the selection of alternative gases,an coordinated regulation model for Environment-friendly gases in DC GILs is *** for future work on this topic are also presented.

关键词： Environmental friendly insulating gas gas-insulated transmission line high-voltage direct-current transmis-sion sulfur hexafluoride

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Mantle sources of Cenozoic volcanoes around the South China Sea revealed by geochemical and isotopic data using the principal component analysis

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Journal of Oceanology and Limnology 2023年第2期41卷 562-574页

作者： Shuangshuang CHEN Zewei WANG Rui GAO Yongzhang ZHOU School of Earth Sciences and Engineering Sun Yat-sen UniversityGuangzhou 510275China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China Guangdong Provincial Key Lab of Geological Processes and Mineral Resources Guangzhou 510275China State Key Laboratory of Marine Environmental Science Xiamen UniversityXiamen 361102China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055China State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Principal component analysis(PCA)was employed to determine the implications of geochemical and isotopic data from Cenozoic volcanic activities in the Southeast Asian region,including China(South China Sea(SCS),Hainan Island,Fujian-Zhejiang coast,Taiwan Island),and parts of Vietnam and *** analyzed 15 trace element indicators and 5 isotopic indicators for 623 volcanic rock samples collected from the study *** principal components(PCs)were extracted by PCA based on the trace elements and Sr-Nd-Pb isotopic ratios,which probably indicate an enriched oceanic island basalt-type mantle plume and a depleted mid-ocean ridge basalt-type spreading *** results show that the influence of the Hainan mantle plume on younger volcanic activities(<13 Ma)is stronger than that on older ones(>13 Ma)at the same location in the Southeast Asian *** was employed to verify the mantle-plume-ridge interaction model of volcanic activities beneath the expansion center of SCS and refute the hypothesis that the tension of SCS is triggered by the Hainan *** study reveals the efficiency and applicability of PCA in discussing mantle sources of volcanic activities;thus,PCA is a suitable research method for analyzing geochemical data.

关键词： volcanic rocks geochemical indicators mantle source principal component analysis South China Sea

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Ultra‑High Sensitivity Anisotropic Piezoelectric Sensors for Structural Health Monitoring and Robotic Perception

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Nano-Micro Letters 2025年第2期17卷 432-446页

作者： Hao Yin Yanting Li Zhiying Tian Qichao Li Chenhui Jiang Enfu Liang Yiping Guo State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Beijing Vacuum Electronics Research Institute Beijing 100015People’s Republic of China Fundamental Science On Vibration Shock and Noise LaboratoryState Key Laboratory of Mechanical System and VibrationSchool of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Monitoring minuscule mechanical signals,both in magnitude and direction,is imperative in many application scenarios,e.g.,structural health monitoring and robotic sensing ***,the piezoelectric sensor struggles to satisfy the requirements for directional recognition due to the limited piezoelectric coefficient matrix,and achieving sensitivity for detecting micrometer-scale deformations is also ***,we develop a vector sensor composed of lead zirconate titanate-electronic grade glass fiber composite filaments with oriented arrangement,capable of detecting minute anisotropic *** as-prepared vector sensor can identify the deformation directions even when subjected to an unprecedented nominal strain of 0.06%,thereby enabling its utility in accurately discerning the 5μm-height wrinkles in thin films and in monitoring human pulse *** ultra-high sensitivity is attributed to the formation of porous ferroelectret and the efficient load transfer efficiency of continuous lead zirconate titanate ***,when integrated with machine learning techniques,the sensor’s capability to recognize multi-signals enables it to differentiate between 10 types of fine textures with 100%*** structural design in piezoelectric devices enables a more comprehensive perception of mechanical stimuli,offering a novel perspective for enhancing recognition accuracy.

关键词： Flexible piezoelectric filaments Anisotropic Ultra-high sensitivity Structural health detection Texture recognition

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Ballistic performance of CFRP under normal and oblique impacts by square fragments: Experimental, numerical, and theoretical investigations

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Thin-Walled Structures 2025年 215卷

作者： Feng, Bo Dong, Yongxiang Min, Qiang Liu, Jian Shi, Xinping Tian, Yumo An, Fengjiang State Key Laboratory of Explosion Science and Safety Protection Beijing Institute of Technology Beijing 100081 China National Key Laboratory of Digital and Agile Aircraft Design Chengdu Aircraft Design & Research Institute Chengdu610091 China Beijing Institute of Electronic System Engineering Beijing 1000854 China

High-performance carbon fibre-reinforced polymer (CFRP) composites are commonly used as external protective structures in military and aerospace applications and are frequently subjected to impact from fragments or projectiles. This study investigated the damage mechanisms of CFRP laminates under normal and oblique impacts from square fragments. Impact tests were conducted on 3–9 mm CFRP laminates using 4 g and 7 g square fragments at velocities ranging from 100 to 1300 m/s and impact angles from 0° to 60° Finite element simulations based on yarn-scale models were also performed. The results revealed that under oblique penetration conditions, the fragment edge initially contacting the target plate caused deeper shear damage. An analytical model was developed to predict the residual velocity of the fragments and the ballistic limit velocity (BLV) of the CFRP laminates. The average error between the model predictions and experimental results was 8.42 %, whereas that between the predictions and simulation results was 3.69 %. Interestingly, the analysis revealed a non-zero minimum resistance angle for the laminate under square fragment impact, at which the BLV of the target plate was minimised. The predicted distribution range of the minimum resistance angle in this study was 23–28° The developed predictive model and identified "minimum resistance angle" provide theoretical foundations for protective engineering design, bridging laboratory research to real-world high-risk applications such as military and aerospace. © 2025 Elsevier Ltd

关键词： Military applications

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Exploration of the application of optimisation algorithm using stochastic gradient descent method in satellite resource allocation

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Applied Mathematics and Nonlinear Sciences 2024年第1期9卷

作者： Zhao, Demin Xiong, Wei Shi, Jinjing Science and Technology on Complex Electronic System Simulation Laboratory University of Aerospace Engineering Beijing101400 China Dfh Satellite CO. Ltd Beijing100080 China North Automatic Control Technology Institute Shanxi Taiyuan030006 China

With the popularization and development of communication technology, the resource allocation problem of satellites has become a hot research topic. This study proposes a model for satellite resource allocation through the development of a beam mobilization system model and problem modeling. Then, on the basis of the linear stochastic gradient descent method, the classification accuracy of the algorithm is improved by adjusting the algorithm-solving method. Then its weight assignment method is improved to get the improved weighted linear stochastic gradient descent method. Using the optimized weighted linear stochastic gradient descent method to solve the satellite resource allocation problem from the perspective of the original problem, a model based on IWLSGD is designed and tested for performance. Through simulation experiments, the beam allocation service value of the satellite resource allocation model in this paper is 193, which is 4.32% and 3.21% higher than that of LSGD and WLSGD, respectively, and iterative convergence is faster, and its operation time and service value performs the best under different numbers of communication time slots. The system revenue, system access success rate, and system satisfaction under the interference environment between LEO and GEO are maintained at 15208, 0.8~1.0, and 85%, and keep around 7500, 1, and 75% under 5G base station interference. The satellite resource allocation model in this paper can effectively improve the utilization efficiency of communication resources and better adapt to dynamically changing interference scenarios. © 2024 Demin Zhao et al., published by Sciendo.

关键词： Resource allocation

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Carbon-neutral pathway to mitigating transport-power grid cross-sector effects

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The Innovation 2024年第3期5卷 27-29页

作者： Jing Ma Huiwen Kong Jianxiao Wang Haiwang Zhong Bo Li Jie Song Daniel M.Kammen State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources School of Electrical and Electronic EngineeringNorth China Electric Power UniversityBeijing 102206China National Engineering Laboratory for Big Data Analysis and Applications Peking UniversityBeijing 100871China Peking University Ordos Research Institute of Energy Ordos 017000China State Key Laboratory of Power Systems and Generation Equipment Department of Electrical EngineeringTsinghua UniversityBeijing 100084China School of Electrical Engineering Guangxi UniversityNanning 530004China Department of Industrial Engineering and Management College of EngineeringPeking UniversityBeijing 100871China Energy and Resources Group and Goldman School of Public PolicyUniversity of CaliforniaBerkeleyBerkeleyCA 94720USA

Dear Editor,The growing demand for transportation energy has brought increasing challenges to reducing greenhouse gas ***,many countries or regions have proposed solutions to achieve carbon-neutral transportation such as the rapid expansion of the global electric vehicle(EV)***,these benefits are not *** the goal of decarbonization in electricity is achieved,the“pseudo net zero emissions”effect of the transportation sector will inevitably be accompanied by a quiet shifting of carbon responsibility.1 This shift is undoubtedly fatal for both net zero emissions at the national level and carbon responsibility at the industry level;however,the corresponding effects have not yet been clarified.

关键词： neutral doubt shifting

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Quantification of human and climate contributions to multi-dimensional hydrological alterations:A case study in the Upper Minjiang River,China

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Journal of Geographical Sciences 2021年第8期31卷 1102-1122页

作者： ZHANG Yuhang YE Aizhong YOU Jinjun JING Xiangyang State Key Laboratory of Earth Surface Processes and Resource Ecology Institute of Land Surface System and Sustainable DevelopmentFaculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China POWERCHINA Chengdu Engineering Corporation Limited Chengdu 611130China

Dual factors of climate and human on the hydrological process are reflected not only in changes in the spatiotemporal distribution of water resource amounts but also in the various characteristics of river flow regimes. Isolating and quantifying their contributions to these hydrological alterations helps us to comprehensively understand the response mechanism and patterns of hydrological process to the two kinds of factors. Here we develop a general framework using hydrological model and 33 indicators to describe hydrological process and quantify the impact from climate and human. And we select the Upper Minjiang River(UMR) as a case to explore its feasibility. The results indicate that our approach successfully recognizes the characteristics of river flow regimes in different scenarios and quantitatively separates the climate and human contributions to multi-dimensional hydrological alterations. Among these indicators, 26 of 33 indicators decrease over the past half-century(1961–2012) in the UMR, with change rates ranging from 1.3% to 33.2%, and the human impacts are the dominant factor affecting hydrological processes, with an average relative contribution rate of 58.6%. Climate change causes an increase in most indicators, with an average relative contribution rate of 41.4%. Specifically, changes in precipitation and reservoir operation may play a considerable role in inducing these alterations. The findings in this study help us better understand the response mechanism of hydrological process under changing environment and is conducive to climate change adaptation, water resource planning and ecological construction.

关键词： hydrological alterations Minjiang River Basin quantitative assessment climate change direct human impacts

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Hybrid Impedance Reshaping Method of Grid-Connected Inverters in Weak Grid

Hybrid Impedance Reshaping Method of Grid-Connected Inverter...

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2023 Power Electronics and Power system Conference, PEPSC 2023

作者： Zheng, Weike Wang, Haijiao Xie, Bao Mao, Meiqin China Electric Power Research Institute State Key Laboratory of Operation and Control of Renewable Energy & Storage Systems Beijing China Photovoltaic System Engineering Research Center Ministry of Education Hefei University of Technology Hefei China

ISBN: (纸本)9798350341294

Both the phase-locked loop (PLL) and the common coupling point (PCC) voltage feedforward may have impacts on the inverter system stability in weak grid. Therefore, a hybrid impedance reshaping control strategy is proposed in the paper. Firstly, the inverter impedance model is established. Next, the system stability is analyzed under weak grid, reflecting on the influence of PLL and the PCC voltage feedforward. Then, to improve the inverter system stability, the band-pass filter is added to the feedforward branch of PCC voltage, since it can attenuate the influence of unstable factors. Moreover, a new phase-locked loop structure containing a first-order decoupled complex filter is proposed, taking into account the fundamental positive voltage extraction characteristics of the first-order decoupled complex filter. The parameters of the hybrid impedance reshaping strategy are designed in detail. Finally, simulation is carried out to prove the theory analysis and hybrid impedance reshaping strategy in the paper. © 2023 IEEE.

关键词： Phase locked loops

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Perovskite films with gradient bandgap for self-powered multiband photodetectors and spectrometers

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Nano Research 2023年第7期16卷 10256-10262页

作者： Chuantian Zuo Lixiu Zhang Xiyan Pan He Tian keyou Yan Yuanhang Cheng Zhiwen Jin Chenyi Yi Xiaoliang Zhang Wu-Qiang Wu Qinye Bao Liyuan Han Liming Ding Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190China School of Physics and Electronic Science East China Normal UniversityShanghai 200241China School of Integrated Circuits Tsinghua UniversityBeijing 100084China School of Environment and Energy South China University of TechnologyGuangzhou 510000China School of New Energy Nanjing University of Science and TechnologyJiangyin 214443China School of Physical Science and Technology Lanzhou UniversityLanzhou 730000China State Key Laboratory of Power System Department of Electrical EngineeringTsinghua UniversityBeijing 100084China School of Materials Science and Engineering Beihang UniversityBeijing 100191China School of Chemistry Sun Yat-sen UniversityGuangzhou 510006China State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Semiconductor Materials Science Beijing Key Laboratory of Low Dimensional Semiconductor Materials and DevicesInstitute of SemiconductorsChinese Academy of SciencesBeijing 100083China

Bandgap-graded materials present varying spectral responses at different positions,making them possible to be used as an alternative to photoactive materials array in multi-spectral responsive devices,thus miniaturizing the ***,the preparation of bandgap-graded materials usually requires complicated deposition *** we report a facile lowtemperature solution process to make films with lateral bandgap gradients,which form spontaneously via self-spreading and interdiffusion of *** show lead halide perovskite films with MAPbCl_(3)-MAPbBr_(3)and MAPbBr_(3)-MAPbI_(3)gradients,which exhibit light absorption onsets ranging from 410 to 781 *** bandgap-graded films were used to make self-powered multiband photodetectors,which show different spectral responses at different positions without applying bias ***,self-powered spectrometers were made by using the multiband photodetectors.

关键词： self-spreading interdiffusion bandgap-graded perovskite multiband photodetectors self-powered spectrometers

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