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Requirement-Oriented TT&C Method for Satellite Based on BDS-3 Short-Message Communication system

Space(Science & Technology) 2023年第1期3卷 311-324页

作者： Chao Li Peijie Liu Shiyuan Fu Yiwen Jiao Wei Zhang Department of Electronic and Optical Engineering Space Engineering UniversityBeijingChina Key Laboratory of Intelligent Space TT&C and Operation(Space Engineering University) Ministry of EducationBeijingChina State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System LuoyangChina Xi’an Satellite Control Center Xi’anChina

With the increasing number of satellites being launched in China,the demand for Telemetry,Tracking,and Command(TT&C)resources is also *** of the global coverage and resource requirements of TT&C management,this paper proposes a TT&C scheme based on the Global Short-Message Communication system(GSMCS)of the BeiDou-3 Navigation Satellite system(BDS-3).The system composition,workflow,and functions of satellite TT&C are analyzed using the GSMCS of *** the coverage analysis of the Medium Earth Orbit(MEO)constellation of BDS-3,scheme’s applicability is pointed out,and the correctness of the analysis results is verified via *** value range of the link distance is derived by calculating the range of the distance variation between any 2 satellites in the BDS-3 MEO constellation and combining the intersatellite routing *** calculation results show that the response time range of the autonomous request management application of in-orbit satellites based on the GSMCS of BDS-3 is 1.407 to 2.448 *** can meet the requirements of TT&C service.

关键词： Message Command service

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Preventive Control Method of Improving Transient Voltage Stability for Power system Based on the Attention of CNN

Preventive Control Method of Improving Transient Voltage Sta...

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2023 IEEE Sustainable Power and Energy Conference, iSPEC 2023

作者： Li, Zhendong Yan, Jiongcheng Liu, Yutian Li, Li Qu, Hanbing The Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Shandong University Jinan China State Grid Jinan Power Supply Company Jinan China

ISBN: (纸本)9798350322699

The widespread integration of renewable generation and the changes in load structure bring significant challenges to the transient voltage stability of large-scale power systems. In order to achieve fast decision of preventive control for improving transient voltage stability, this paper proposes a preventive control method based on the attention of Convolutional Neural Network (CNN). An optimization decision model is established, which not only considers multiple traditional constraints but also introduces the model attention indicator based on Gradient-weighted Class Activation Mapping (Grad-CAM), enabling a more targeted improvement of transient voltage stability. The proposed indicator is capable of extracting the knowledge learned by CNN-based transient voltage assessment model, and utilizing it to guide the optimization decision-making of preventive control. Simulation results of provincial grid of eastern China demonstrate that the optimized control scheme can effectively enhance the transient voltage stability of power systems. © 2023 IEEE.

关键词： model attention indicator power system preventive control transient voltage stability

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Squeezing More Past Knowledge for Online Class-Incremental Continual Learning

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IEEE/CAA Journal of Automatica Sinica 2023年第3期10卷 722-736页

作者： Da Yu Mingyi Zhang Mantian Li Fusheng Zha Junge Zhang Lining Sun Kaiqi Huang the State Key Laboratory of Robotics and System Harbin Institute of Technology(HIT)Harbin 150080China Center for Research on Intelligent System and Engineering Institute of AutomationChinese Academy of Sciences(CASIA)Beijing 100190 School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China Center for Research on Intelligent System and Engineering Institute of AutomationChinese Academy of Sciences(CASIA)Beijing 100190the School of Artificial IntelligenceUniversity of Chinese Academy of SciencesBeijing 100049 the CAS Center for Excellence in Brain Science and Intelligence Technology Shanghai 200031China IEEE

Continual learning(CL)studies the problem of learning to accumulate knowledge over time from a stream of data.A crucial challenge is that neural networks suffer from performance degradation on previously seen data,known as catastrophic forgetting,due to allowing parameter *** this work,we consider a more practical online class-incremental CL setting,where the model learns new samples in an online manner and may continuously experience new ***,prior knowledge is unavailable during training and *** works usually explore sample usages from a single dimension,which ignores a lot of valuable supervisory *** better tackle the setting,we propose a novel replay-based CL method,which leverages multi-level representations produced by the intermediate process of training samples for replay and strengthens supervision to consolidate previous ***,besides the previous raw samples,we store the corresponding logits and features in the ***,to imitate the prediction of the past model,we construct extra constraints by leveraging multi-level information stored in the *** the same number of samples for replay,our method can use more past knowledge to prevent *** conduct extensive evaluations on several popular CL datasets,and experiments show that our method consistently outperforms state-of-the-art methods with various sizes of episodic *** further provide a detailed analysis of these results and demonstrate that our method is more viable in practical scenarios.

关键词： Catastrophic forgetting class-incremental learning continual learning(CL) experience replay

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Electromagnetic Transient Modeling and Real-time Simulation Based on state-space Equations 4

Electromagnetic Transient Modeling and Real-time Simulation ...

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4th International Conference on New Energy and Power Engineering, ICNEPE 2024

作者： Guo, Tianyu Hu, Binjiang Luo, Hui Tu, Liang Zhao, Yanjun Hu, YuFeng China Southern Power Grid State Key Laboratory of Hvdc Electric Power Research Institute Guangdong China Guangdong Provincial Key Laboratory of Intelligent Operation and Control for New Energy Power System Guangdong China China Southern Power Grid Csg Key Laboratory for Power System Simulation Electric Power Research Institute Guangdong China China Southern Power Grid Co. Ltd China

ISBN: (纸本)9798331516086

Due to the different output characteristics of different components of the power system, the simulation results of its output deviate from the actual situation. Therefore, the electromagnetic transient modeling and real-time simulation based on the state space equation are proposed. From the perspective of rectifier, DC transmission line, inverter and control system, the composition of the state space model of the complete power system and the output characteristics of each part in the operation process are analyzed. In the test results, the design method can achieve a stable fit between the real-time simulation results of voltage waveform containing two VSC modules and the actual situation. © 2024 IEEE.

关键词： Electromagnetic transients

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Synchronization Stability Analysis of Wind Farms Integrated MMC-HVDC system

Synchronization Stability Analysis of Wind Farms Integrated ...

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2023 International Conference on Power system Technology, PowerCon 2023

作者： Li, Li Qin, Changlong Kan, Changtao Yang, Jialun Li, Guanqun State Grid Jinan Power Supply Company Jinan China Shandong University Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Jinan China

ISBN: (纸本)9798350300222

High-voltage direct current (HVDC) based on modular multilevel converter (MMC) is an efficient way to integrate wind farms. However, following short-circuit fault on transmission line, wind turbines (WTs) may lose synchronization with sending-end MMC. As a result, delivery and consumption of wind power are under risk. This paper investigates the mechanism of synchronous instability of wind farm integrated MMC-HVDC system under the severe grid faults. First, a synchronization stability model of the whole is stablished, the existing of stable equilibrium points (SEPs) and the damping characteristic of the whole system are analyzed. Then, a synchronization stability enhancement strategy is proposed based on the coordination of WT and MMC. Last, the effectiveness of proposed strategy is verified by time-domain simulation. © 2023 IEEE.

关键词： Transient analysis

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CASKA-CRT: Chinese Remainder Theorem Empowered Certificateless Aggregate Signcryption Scheme with key Agreement in IoVs

IEEE Transactions on Intelligent Vehicles

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IEEE Transactions on intelligent Vehicles 2024年 1-16页

作者： Hou, Yingzhe Cao, Yue Xiong, Hu Sun, Zhili Mumtaz, Shahid Tian, Daxin School of Cyber Science and Engineering Wuhan University Wuhan China School of Information and Software Engineering University of Electronic Science and Technology of China Chengdu China Institute of Communication Systems University of Surrey Guildford U.K Department of Applied Informatics Silesian University of Technology Akademicka Gliwice Poland State Key Laboratory of Vehicle-Infrastructure Integrated ITS the State Key Laboratory of Intelligent Transportation System and the School of Transportation Science and Engineering Beihang University Beijing China

To enhance the privacy of messages in Internet of Vehicles (IoVs), it is critical to preserve the communication security between Road Side Unit (RSU) and numerous vehicles. The primitive of signcryption is introduced to guarantee the confidentiality, integrity and unforgeability of transmitted messages. Nevertheless, the existing signcryption schemes fail to achieve a balance between security and efficiency. In this paper, we construct a Chinese remainder theorem (CRT) empowered certificateless aggregate signcryption scheme with key agreement (CASKA-CRT). As the vehicle joins and leaves dynamically, the proposed scheme can ensure the dynamic security via one modulo division operation. Besides, the certificateless aggregate signcryption and key agreement mechanisms are embedded. The former idea can both address the certificate management and key escrow problems, while the latter technology can create authentication as a premise of secure communication. Based on this construction, the hash-to-group operation and bilinear pairing are avoided, to realize a faster verification with the increased number of messages. Moreover, the security of proposed scheme is proved under the random oracle model. Finally, the performance analysis demonstrates the advantage of CASKA-CRT in terms of security and reliability over related works. IEEE

关键词： Public key cryptography

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Data quantity governance for machine learning in materials science

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National Science Review 2023年第7期10卷 234-250页

作者： Yue Liu Zhengwei Yang Xinxin Zou Shuchang Ma Dahui Liu Maxim Avdeev Siqi Shi School of Computer Engineering and Science Shanghai University Shanghai Engineering Research Center of Intelligent Computing System Australian Nuclear Science and Technology Organisation School of Chemistry The University of Sydney State Key Laboratory of Advanced Special Steel School of Materials Science and Engineering Shanghai University Materials Genome Institute Shanghai University

Data-driven machine learning(ML) is widely employed in the analysis of materials structure-activity relationships,performance optimization and materials design due to its superior ability to reveal latent data patterns and make accurate ***,because of the laborious process of materials data acquisition,ML models encounter the issue of the mismatch between a high dimension of feature space and a small sample size(for traditional ML models) or the mismatch between model parameters and sample size(for deep-learning models),usually resulting in terrible ***,we review the efforts for tackling this issue via feature reduction,sample augmentation and specific ML approaches,and show that the balance between the number of samples and features or model parameters should attract great attention during data quantity *** this,we propose a synergistic data quantity governance flow with the incorporation of materials domain *** summarizing the approaches to incorporating materials domain knowledge into the process of ML,we provide examples of incorporating domain knowledge into governance schemes to demonstrate the advantages of the approach and *** work paves the way for obtaining the required high-quality data to accelerate materials design and discovery based on ML.

关键词： machine learning data governance data quantity materials science

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Stabilization of zinc anode by trace organic corrosion inhibitors for long lifespan

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Chinese Chemical Letters 2025年第3期36卷 538-543页

作者： Wenfeng Shao Chuanlin Li Chenggang Wang Guangsen Du Shunshun Zhao Guangmeng Qu Yupeng Xing Tianshuo Guo Hongfei Li Xijin Xu School of Physics and Technology University of JinanJi’nan 250022China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China School of Chemistry and Chemical Engineering Shandong UniversityJi’nan 250100China School of System Design and Intelligent Manufacturing Southern University of Science and TechnologyShenzhen 518000China

Aqueous zinc-ion batteries are highly favored for their enhanced safety and reduced ***,there exist challenges including zinc dendrite,hydrogen evolution,and surface corrosion to be *** electrolyte additives is a highly convenient approach to solving zinc anode-related *** by industrial corrosion protection,a trace amount of the corrosion inhibitor urotropine(URT)is used as an electrolyte additive to protect the zinc *** calculation and experimental analysis confirm the adsorption of URT molecules onto the surface of Zn,which inhibits hydrogen *** adsorption further leads to the formation of an inorganic-organic bilayer solid electrolyte interface(SEI)on the surface of the zinc anode,effectively protecting the Zn anode from corrosion,hydrogen evolution and zinc *** presence of SEI enables symmetrical Zn//Zn cells to exhibit a long cycling performance of 1750 h at 1mA/cm^(2)and an average coulombic efficiency of 99.0%at 1mA/cm^(2)in Zn//Cu *** being coupled with polyaniline(PANI),the Zn//PANI full battery displays excellent cycle stability and specific capacity.

关键词： Solid electrolyte interface Aqueous zinc-ion battery Corrosion inhibitors Electrolyte additive Zinc anode

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Long-life Design and Experimental Verification of Ball Screw for Spacecraft Mechanism 7

Long-life Design and Experimental Verification of Ball Screw...

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7th International Conference on Electromechanical Control Technology and Transportation, ICECTT 2022

作者： Zhang, Wenming Zhang, Yun Chen, Ming Zeng, Lei Gao, Sheng Jiang, Xufu Beijing Key Laboratory of Intelligent Space Robotic Systems Technology and Applications Beijing Institute of Spacecraft System Engineering Beijing China Beijing Satellite Manufacturing Limited Company Beijing China

ISBN: (纸本)9781510656659

The ball screw is a commonly used transmission component. When applied to the spacecraft mechanism, it is necessary to comprehensively consider space environmental factors such as on-orbit high and low temperature, vacuum, atomic oxygen, electron irradiation, single particle, ultraviolet and infrared irradiation. In view of the long-life application requirements of ball screws for spacecraft mechanism, the factors affecting the life of the ball screws are analyzed. Two design schemes are proposed according to the lubrication method of the ball screws and the material of ball for a ball screws of a certain spacecraft mechanism. The design scheme of ceramic ball + raceway sputtering MoS2 lubrication has been confirmed by the test. The design can work for no less than 7000 times under the specified load, which meets the requirements of the flight model on-orbit. Through the ball screw long-life test, it can be seen that the load capacity and service life of the solid lubricated ball screw are significantly reduced. In the development process of the spacecraft mechanism ball screw, a special life test must be carried out to verify whether the ball screw can meet the on-orbit requirements. © 2022 SPIE

关键词： Layered semiconductors

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Understanding microstructure-property relationships of HPDC Al-Si alloy based on machine learning and crystal plasticity simulation

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Advances in Manufacturing 2024年第3期12卷 497-511页

作者： Qiang-Qiang Zhai Zhao Liu Ping Zhu State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai200240People’s Republic of China National Engineering Research Center of Automotive Power and Intelligent Control Shanghai Jiao Tong UniversityShanghai200240People’s Republic of China School of Design Shanghai Jiao Tong UniversityShanghai200240People’s Republic of China

Al-Si alloys manufactured via high-pressure die casting(HPDC)are suitable for a wide range of ***,the heterogeneous microstructure and unpredictable pore distribution of Al-Si high-pressure die castings result in significant variations in the mechanical properties,thus leading to a complicated microstructure-property relationship that is difficult to ***,a computational framework incorporating machine learning and crystal plasticity method is *** framework aims to provide a systematic and comprehensive understanding of this relationship and enable the rapid prediction of macroscopic mechanical properties based on the ***,we select eight variables that can effectively characterize the microstructural features and then obtain their statistical ***,based on 160 samples obtained via the Latin hypercube sampling method,representative volume elements are constructed,and the crystal plasticity fast Fourier transformation method is executed to obtain the macroscopic mechanical ***,the yield strength,elastic modulus,strength coefficient,and strain-hardening exponent are used to characterize the stress-strain curve,and Gaussian process regression models and microstructural variables are ***,sensitivity and univariate analyses based on these machine-learning models are performed to obtain insights into the microstructure-property relationships of the HPDC Al-Si *** results show that the Gaussian process regression models exhibit high accuracy(R^(2) greater than 0.84),thus confirming the viability of the proposed *** results of sensitivity analysis indicate that the pore size exerts the most significant effect on the mechanical ***,the proposed framework can not only be transferred to other alloys but also be employed for material design.

关键词： High-pressure die casting(HPDC) Machine learning Crystal plasticity Aluminum alloys

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