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Unified numerical predictor-corrector guidance based on characteristic model

中国空间科学技术（中英文） 2024年第4期44卷 40-49页

作者： MENG Bin ZHANG Hangning ZHAO Yunbo Beijing Institute of Control Engineering Beijing 100094China National Key Laboratory of Space Intelligent Control Beijing 100094China University of Science and Technology of China Hefei 230026China

Aerocapture is one of the key technologies for low-cost transportation,with high demands of autonomy,accuracy,and robustness of guidance and control,due to its high reliability requirements for only one chance of trying.A unified numerical predictor-corrector guidance method based on characteristic models for aerocapture is *** numerical predictor-corrector guidance method is used to achieve autonomy and high accuracy,and the characteristic model control method is introduced to achieve *** the same time,by transforming path constraints,characteristic model equations including apogee deviation and altitude differentiation are *** on the characteristic model equations,a unified guidance law which can satisfy path constraints and guidance objectives simultaneously is *** guidance problems,guidance deviation is not directly obtained from the output of the dynamics at present,but is calculated through integral and algebraic ***,the method of directly discretizing differential equations cannot be used to establish characteristic models,which brings great difficulty to characteristic modeling.A method for characteristic modeling of guidance problems is proposed,and convergence analysis of the proposed guidance law is also ***,a joint numerical simulation of guidance and control considering navigation deviation and various uncertainties is conducted to verify the effectiveness of the proposed *** proposed unified method can be extended to general aerodynamic entry guidance designs,providing theoretical and methodological support for them.

关键词： aerocapture path constraint characteristic model unified numerical predictor-corrector guidance convergence

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Graphene binding on black phosphorus enables high on/off ratios and mobility

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national science Review 2024年第2期11卷 188-195页

作者： Fanrong Lin Zhonghan Cao Feiping Xiao Jiawei Liu Jiabin Qiao Minmin Xue Zhili Hu Ying Liu Huan Lu Zhuhua Zhang Jens Martin Qingjun Tong Wanlin Guo Yanpeng Liu Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education State Key Laboratory of Mechanics and Control of Mechanical Structures and Institute for Frontier Science Nanjing University of Aeronautics and Astronautics Centre for Advanced 2D Materials National University of Singapore School of Physics and Electronics Hunan University Centre for Quantum Physics Key Laboratory of Advanced Optoelectronic Quantum Architecture and MeasurementSchool of PhysicsBeijing Institute of Technology Leibniz Institute für Kristallzüchtung

Graphene is one of the most promising candidates for integrated circuits due to its robustness against short-channel effects, inherent high carrier mobility and desired gapless nature for Ohmic contact, but it is difficult to achieve satisfactory on/off ratios even at the expense of its carrier mobility, limiting its device applications. Here, we present a strategy to realize high back-gate switching ratios in a graphene monolayer with well-maintained high mobility by forming a vertical heterostructure with a black phosphorus multi-layer. By local current annealing, strain is introduced within an established area of the graphene, which forms a reflective interface with the rest of the strain-free area and thus generates a robust off-state via local current depletion. Applying a positive back-gate voltage to the heterostructure can keep the black phosphorus insulating, while a negative back-gate voltage changes the black phosphorus to be conductive because of hole accumulation. Then, a parallel channel is activated within the strain-free graphene area by edge-contacted electrodes, thereby largely inheriting the intrinsic carrier mobility of graphene in the on-state. As a result, the device can provide an on/off voltage ratio of >10～3 as well as a mobility of ～8000 cm2V-1s-1at room temperature, meeting the low-power criterion suggested by the International Roadmap for Devices and Systems.

关键词： graphene on/off ratio mobility black phosphorus reflective interface

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Optical performance monitoring of mode division multiplexing signal based on multi-task convolutional neural network 7

Optical performance monitoring of mode division multiplexing...

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7th Optics Young Scientist Summit, OYSS 2024

作者： He, Ting Chang, Huan Gao, Ran Wang, Fei Guo, Dong Beijing Institute of Technology No.5 Zhongguancun South Street Haidian District Beijing100081 China National Key Laboratory of Science and Technology on Space-Born Intelligent Information Processing Beijing China

ISBN: (数字)9781510688377

ISBN: (纸本)9781510688360

Mode division multiplexing (MDM) optical fiber communication technology enhances bandwidth utilization and communication capacity to address the increasing demand for high-capacity data transmission in the era of rapid network traffic growth. For MDM optical fiber communication systems affected by various impairments, optical performance monitoring (OPM) can effectively characterize the impairments in received optical signals, directly reflecting the transmission signal state and channel conditions, and help ensure efficient and stable network operation. In this paper, we propose a multi-task convolutional neural network (MT-CNN) aided OPM method for MDM signals. The proposed MTCNN combines convolutional neural networks and a multi-task learning framework to extract the transmission link information and predict the optical signal-to-noise ratio (OSNR) of few-mode channels synchronously. Simulation results show that the proposed MT-CNN-based OPM scheme can achieve accurate OSNR performance evaluation for MDM fiber transmission signals. © 2025 SPIE.

关键词： Convolutional neural networks

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Network synchronizability enhancement viaadding antagonistic interactions

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Autonomous intelligent Systems 2024年第1期4卷 1-7页

作者： Yue Song Xiaoqin Liu Dingmei Wang Pengfei Gao Mengqi Xue Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghai201210China Shanghai Research Institute for Intelligent Autonomous Systems Tongji UniversityShanghai201210China Department of Control Science and Engineering Tongji UniversityShanghai201210China National Key Laboratory of Autonomous Intelligent Unmanned Systems Tongji UniversityShanghai201210China Lanzhou Longneng Electric Power Technology Company Lanzhou730070China

We discover a“less-is-more”effect that adding local antagonistic interactions(negative edge weights)can enhance the overall synchronizability of a dynamical network *** explain this seemingly counterintuitive phenomenon,a condition is established to identify those edges the weight reduction of which improves the synchronizability index of the underlying *** further reveal that this condition can be interpreted from the perspective of resistance distance and network community *** obtained result is also verified via numerical experiments on a 14-node network and a 118-node *** brings new thoughts and inspirations to the future directions of optimal network design problems.

关键词： Synchronizability Complex network Laplacian matrix Antagonistic interaction

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Acute Effects of Exposure to Fine Particulate Matter and Its Constituents on Sex Hormone Among Postmenopausal Women — Beijing, Tianjin, and Hebei PLADs, China, 2018–2019

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China CDC weekly 2024年第13期6卷 249-253,I0001-I0004页

作者： Yanlin Tian Jiaonan Wang Jianlong Fang Chen Chen Feng Zhao Yi Zhang Peng Du Yawei Li Wanying Shi Yuanyuan Liu Enmin Ding Song Tang Xu Yue Xiaoming Shi Chinese Research Academy of Environmental Sciences BeijingChina Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control(AEMPC)Nanjing University of Information Science&TechnologyNanjing CityJiangsu ProvinceChina China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina Department of Epidemiology and Health Statistics School of Public HealthCapital Medical Universityand Beijing Municipal Key Laboratory of Clinical EpidemiologyBeijingChina National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina

What is already known on this topic?Exposure to fine particulate matter(PM_(2.5))was linked to endocrine hormone disruption in the reproductive ***,it was unclear which specific components of PM_(2.5) were primarily responsible for these *** is added by this report?The study presented the initial epidemiological evidence that brief exposure to PM_(2.5) can elevate estradiol levels in postmenopausal *** particle components had unique effects,with watersoluble ions and specific inorganic elements like Ag,As,Cd,Hg,Ni,Sb,Se,Sn,and Tl potentially playing significant roles in increasing estradiol *** are the implications for public health practice?The study established that the prevalence of air pollution,along with its specific components,has been recognized as a novel risk factor affecting the balance of sex hormones.

关键词： pollution Particulate primarily

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First results of the low energy ion spectrometer onboard a Chinese geosynchronous satellite

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science China(Technological sciences) 2023年第5期66卷 1378-1384页

作者： SHAN Xu MIAO Bin CAO Zhe SUN ZhenYu LI YiRen LIU Kai GUO XingYu QU SanBiao SU ZhenPeng SHEN ChengLong PAN ZongHao LI Xin HAO XinJun YANG XiaoPing TIAN Chao JIANG Yu LIU ShuBin AN Qi CHEN XiangJun WANG YuMing Hefei National Research Center for Physical Sciences at the Microscale Department of Modern PhysicsUniversity of Science and Technology of ChinaHefei230026China CAS Key Laboratory of Geospace Environment School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei230026China State Key Laboratory of Particle Detection and Electronics(IHEP-USTC) Department of Modern PhysicsUniversity of Science and Technology of ChinaHefei230026China Shandong Institute of Space Electronic Technology Yantai264003China State Key Laboratory of Astronautic Dynamics Xi’an Satellite Control CenterXi’an710043China CAS Center for Excellence in Comparative Planetology University of Science and Technology of ChinaHefei230026China

A Chinese geosynchronous satellite was launched on June 23,*** carried a plasma detection package to monitor the space environment around the *** we report the inflight performance of a low energy ion spectrometer(LEIS),one of the primary instruments in the plasma detection package,and its initial observations in *** from the state-of-the-art design of a top-hat electrostatic analyzer cooperated with angular scanning deflectors,three-dimensional measurement of ions in space with a large field of view of 360°×90°and a wide energy range from 50 eV to 25 keV per charge has been *** differential energy flux spectra of ions around the orbit have shown clear signatures of surface charging and storm/substorm ion *** occurrence of surface charging could be caused by the lack of photoemission at the Earth's eclipse(near the midnight)or the storm energetic electron injection at the dawn *** present results demonstrated a good performance of the LEIS payload in flight for monitoring the space ion environment around the *** situ measurements of the LEIS payload provide us an opportunity to understand the magnetospheric ion dynamics and forecast the associate space weather impacts.

关键词： low energy ion spectrometer geosynchronous orbit inflight measurement differential energy flux surface charging storm/substorm

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Robust H∞ Attitude Stabilization for the Cluster Takeover of Non-cooperative Flexible spacecraft 1

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29th International Conference on Computational and Experimental Engineering and sciences, ICCES 2023

作者： Yue, Xiaokui Yang, Ziyu Yu, Hongyu Huang, Panxing Liu, Yuan National Key Laboratory of Aerospace Flight Dynamics School of Astronautics Northwestern Polytechnical University Xi’an710072 China Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control Engineering Beijing100094 China Beijing Institute of Remote Sensing Information Beijing100011 China

ISBN: (数字)9783031449475

ISBN: (纸本)9783031449468

In this paper, a cooperative control scheme based on the small spacecraft cluster is proposed for the takeover control of the failed flexible spacecraft in space. In order to overcome external disturbance, inertia uncertainty and controller gain perturbation, the controller spacecraft calculates the control torque which can stabilize the combined spacecraft in theory, and generates the desired control signal according to the robust H∞ non-fragile control law set in advance. Based on the communication topology, the actuator spacecraft restores the control signal according to the distributed control torque allocation scheme considering the saturation state of all reaction wheels, and implements it to achieve the attitude stabilization and vibration suppression of the combined spacecraft. Simulation results show that the distributed control torque allocation scheme can implement the desired control signal with relatively small error. Under the condition that the external disturbance, controller gain perturbation and inertia uncertainty coexist, the angle and angular velocity of the combined spacecraft can be stabilized quickly. Moreover, the vibration of the flexible appendages can also be suppressed effectively. During the whole takeover control process, the dynamic allocation scheme can always ensure that all reaction wheels of each actuator spacecraft never reach saturation. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2024.

关键词： Flexible spacecraft

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A Dual Network Approach with Enhanced Feature Guidance for SAR-to-Optical Image Translation 2

A Dual Network Approach with Enhanced Feature Guidance for S...

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2nd IEEE International Conference on Signal, Information and Data Processing, ICSIDP 2024

作者： He, Jingfei Mao, Yongfei Zhao, Liangbo Cui, Zihan Wang, Yu Shi, Hao Beijing Institute of Technology National Key Laboratory of Science and Technology on Space-Born Intelligent Information Processing Beijing China China Academy of Space Technology Institute of Remote Sensing Satellite Beijing China China Academy of Space Technology Beijing Institute of Space Mechanics and Electricity Beijing China

ISBN: (纸本)9798331515669

Synthetic Aperture Radar (SAR) images own dominant merits, such as all-weather and all-day working conditions, but it is difficult for unprofessional people to interpret SAR images. Translating SAR images into optical images to assist interpretation can facilitate the transformation of SAR data into usable information. Therefore, an advanced SAR to Optical (S2O) image translation method utilizing a parallel Generative Adversarial Network (GAN) framework was proposed. This method incorporates an optical image reconstruction network alongside the S2O translation network, enhancing the fidelity and color consistency of the translated images. By employing a domain alignment module and a deep supervision feature loss module, the network effectively utilizes abundant optical image features to overcome the scarcity of SAR-optical image pairs. Experiments conducted on the SEN1-2 dataset demonstrate superior performance over existing methods, particularly in preserving detailed structural information in images. © 2024 IEEE.

关键词： Generative adversarial networks

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Swarm-Based Dynamic Coverage of Multi-ASV Systems in the Presence of Measurement Noises

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IEEE Transactions on Vehicular technology 2025年第5期74卷 7237-7250页

作者： Liu, Lu Jiao, Shijian Han, Bing Li, Tieshan Peng, Zhouhua Dalian Maritime University School of Marine Electrical Engineering Dalian116026 China Dalian Key Laboratory of Swarm Control and Electrical Technology for Intelligent Ships Dalian116026 China State Key Laboratory of Maritime Technology and Safety Dalian116026 China Shanghai Ship and Shipping Research Institute National Engineering Research Center of Ship & Shipping Control System Shanghai200135 China University of Electronic Science and Technology of China School of Automation Engineering Chengdu611731 China

This paper is concerned with the dynamic coverage of multiple autonomous surface vehicles (ASVs) in the presence of static and dynamic obstacles, limited communication distance, and measurement noises. A modular control method including planning, guidance, and control is proposed. At the planning level, a swarm-based dynamic coverage strategy is developed to achieve the coverage of a given domain. Both the collision avoidance and connectivity preservation issues are solved by using artificial potential fields. At the kinematic level, novel adaptive line-of-sight guidance laws are presented based on cascade extended state observers (CESOs), such that accurate guidance signals are given by compensating for time-varying sideslip angle and suppressing measurement noises. At the kinetic level, two CESOs are developed to estimate the internal model uncertainties and external environmental disturbance, and antidisturbance kinetic control laws are designed subsequently. The proposed CESOs overcome the noises sensitivity problem of classical observers, and thus facilitate the practical implementation under measurement noises. The input-to-state stability of the closed-loop system is confirmed by the Lyapunov theory and cascade stability theory. Simulation and hardware-in-the-loop experiment results are provided to demonstrate the effectiveness of the proposed swarm-based dynamic coverage method. © 1967-2012 IEEE.

关键词： Velocity measurement

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A SAR Target Recognition Strategy Guided by Electromagnetic Scattering Feature 2

A SAR Target Recognition Strategy Guided by Electromagnetic ...

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2nd IEEE International Conference on Signal, Information and Data Processing, ICSIDP 2024

作者： Yin, Yifei Chen, Liang Liu, Lujiao Meng, Yufan Chen, Fan Shi, Hao National Key Laboratory of Science and Technology on Space-Born Intelligent Information Processing Beijing Institute of Technology Beijing China Chinese Academy of Sciences Aerospace Information Research Institute Beijing China

ISBN: (纸本)9798331515669

SAR target Automatic Target Recognition (ATR) is indispensable in SAR image interpretation. Recently, deep learning technology has been widely used in SAR target recognition tasks. Most networks achieve incremental improvements in target recognition by modifying their structures to extract visual features of targets. However, due to the unique imaging mechanism, relying solely on visual features often leads to the loss of target information. In contrast, the ASC model, which captures the electromagnetic scattering characteristics of the target, plays a crucial role in target recognition tasks. Unfortunately, traditional parameter estimation methods for extracting the ASC model are computationally expensive and time-consuming, making them impractical for real-world applications. To address these issues, we propose a novel target recognition method based on electromagnetic scattering features in this paper. First, a lightweight network-based feature extraction module is designed. Then, the target ASC image is used as the ground truth for guidance, with image intensity and target structure serving as the loss functions during training. Finally, an ASC model-guided feature fusion network is designed, utilizing the fused features for target recognition. On the MSTAR dataset, a visual assessment experiment demonstrated that the proposed feature extraction module effectively extracts electromagnetic scattering features under various operating conditions. Subsequently, in downstream classification tasks, the inclusion of the proposed module resulted in improved accuracy compared to other networks. Additionally, a visualization analysis of the classification network showed that, under the guidance of electromagnetic scattering features, the network achieved good interpretability. © 2024 IEEE.

关键词： Deep learning

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