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arXiv 2022年

作者： Tanaka, Haruaki Yamasaki, Yusuke Yasuda, Satoshi Shiga, Nobuyasu Takizawa, Kenichi Chauvet, Nicolas Horisaki, Ryoichi Naruse, Makoto Department of Information Physics and Computing Graduate School of Information Science and Technology The University of Tokyo Tokyo113-8656 Japan Space-Time Standards Laboratory Electromagnetic Standards Research Center Radio Research Institute National Institute of Information and Communications Technology Koganei184-8795 Japan Sustainable Ict System Laboratory Resilient Ict Research Center Network Research Institute National Institute of Information and Communications Technology Sendai980-0812 Japan

Low latency and reliable information transfer are highly demanded in fifth generation (5G) and beyond 5G wireless communications. A novel delay-bounded wireless media access control (MAC) protocol called Carrier Sense Multiple Access with Arbitration Point (CSMA/AP) was established to strictly ensure the upper boundary of communication delay. CSMA/AP enables collision-free and delay-bounded communications with a simple arbitration mechanism exploiting the precise time synchronization achieved by Wireless Two-Way Interferometry (Wi-Wi). Experimental demonstration and proving the feasibility in wireless environments are among the most critical steps before any further discussion of CSMA/AP and extension to various applications can take in place. In this work described in this paper, we experimentally demonstrated the fundamental principles of CSMA/AP by constructing a star-topology wireless network using software-defined radio terminals combined with precise time synchronization devices. We show that CSMA/AP was successfully operated, even with dynamic changes of the spatial position of the terminal or the capability to accommodate mobility, thanks to the real-time adaption to the dynamically changing environment byWi-Wi. We also experimentally confirmed that the proposed CSMA/AP principle cannot be executed without Wi-Wi, which validates the importance of precise time synchronization. This study paves the way toward realizing delay-bounded wireless communications for future low-latency and highly reliable critical applications. Copyright © 2022, The Authors. All rights reserved.

关键词： Wireless networks

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Design and Experimental Validation of Sealing Assembly for Lunar Regolith Volatile Extraction Heating Furnace

Design and Experimental Validation of Sealing Assembly for L...

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IEEE International Conference on Robotics and Biomimetics

作者： Hongan Zhang Junyue Tang Yinchao Wang Zixiao Lu Bo Wang Miaoyan Cao Shengyuan Jiang Mechanical Engineering Yanshan University Qinhuangdao P. R. China State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin P. R. China Mechatronics Institute Shenyang Aerospace University Shenyang P. R. China National Center for Nanoscience and Technlogy Chinese Academy of Science Beijing P. R. China China Academy of Space Technology Beijing P. R. China

A lunar regolith in-situ analysis payload deploying a mass spectrometer is proposed to exactly detect the water ice of the South Pole of the moon for China future lunar exploration missions. In order to realize the goal, an airtight heating furnace for volatile extraction from lunar regolith is desired. In this paper, sealing methods for lunar regolith volatile in heating furnace to future proposed in-situ sampling and analysis of lunar samples were investigated based on power requirements, furnace closing accuracy requirements, dust tolerance and operation in the Lunar environment. Methods implemented include a balanced metal hollow ring seal, a double channel ferrule tab ring radial seal and a spring energized seal. Comparing the performance of sealing methods under the above conditions, a spring energized seal is selected as the heating furnace seal. The materials and structure of the seal are designed based on the rigidity requirements, leakage rate requirements and working environment requirements. In order to test the sealing performance of seals after repeated sealing in high and low temperature environments, a seal leak detection system was designed. The test results indicate that the seal can meet the sealing performance requirements after repeated sealing at various temperatures.

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Research on the impact of extraterrestrial lava tube environments on human survival and countermeasures

Space Habitation

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space Habitation 2025年第1期1卷

作者： Xingyang She Jiang Wang Weiyang Xu Long Xiao Planetary Science Institute School of Earth Sciences China University of Geosciences Wuhan China Aerospace System Engineering Shanghai Shanghai 201109 China State Key Laboratory of Lunar and Planetary Sciences Space Science Institute Macau University of Science and Technology Macao

Lava tubes, formed by the flow and cooling of volcanic lava, have been discovered on the surfaces of multiple celestial bodies within the solar system. Due to their excellent protection against meteorite impacts, radiation shielding, and stable temperatures, they are considered one of the ideal locations for future extraterrestrial bases. However, achieving long-term human survival in extraterrestrial lava tube environments still faces numerous risks and challenges. The interiors of natural lava tube caves often contain rubble and cracks, requiring pre-treatment work. The vacuum environment is extremely unfavorable for human survival, necessitating sealing and pressurization inside the lava tubes. The caves are in a state of permanent darkness, requiring long-term lighting solutions. While the cave roofs provide shielding from space radiation, they also attenuate radio signals emitted from within. Additionally, long-term survival in enclosed spaces can have negative impacts on both physical and psychological health. Only by comprehensively considering these challenges and adopting appropriate technologies and solutions can humans truly achieve long-term survival and development in extraterrestrial spaces. This paper proposes strategies for utilizing lunar and Martian lava tube caves, focusing on cave treatment and pressurization, lighting and energy supply, communication technologies, and habitation systems, to enable long-term human survival in extraterrestrial environments.

关键词： Lava Tubes Moon Mars Extraterrestrial Bases Risks and Countermeasures

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An Anti-Interference Chaotic Scheme for Cognitive Radio

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Wuhan University Journal of Natural sciences 2020年第5期25卷 435-444页

作者： DUAN Junyi YANG Hua Key Laboratory of Dynamic Cognitive System of Electromagnetic Spectrum Space Nanjing University of Aeronautics and AstronauticsNanjing 210016JiangsuChina Nanjing Institute of Railway Technology Nanjing 210031JiangsuChina School of Electronic Science and Engineering Nanjing University of Posts and TelecommunicationsNanjing 210023JiangsuChina

Chaotic sequence has been applied in Cognitive Radio(CR)to exert the enormous potential spectral utilization and enhance the transmission ***,since there is not strict orthogonality between chaotic signals,intra-signal interference(ISI)will be introduced into the ***,an anti-interference orthogonal-frequency-division-multiplexing(OFDM)chaotic modulation named Walsh-sequence chaotic CR(WS-CCR)is proposed for cognitive *** constructing the strictly orthogonal chaotic signal based on Walsh sequence,the ISI component,which is produced by frequency offset in previous CR,can be eliminated during the ***,the chaotic sequence can also be applied to scramble subcarriers to relieve the interference caused by malicious *** approximation method is adopted to obtain the exact performance analysis of WS-CCR over Additive White Gaussian Noise(AWGN)channel and Rayleigh multipath fading *** show that,with subcarriers scrambling by chaotic sequence,anti-interference performance and transmitting security can be signi?cantly improved in ***,due to the absence of ISI component,the bit-error ratio(BER)performance of WS-CCR is better than that of the previous CR system.

关键词： chaotic cognitive radio Walsh-sequence subcarriers scrambling

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Survival of the magnetotactic bacterium Magnetospirillum gryphiswaldense exposed to Earth’s lower near space

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science Bulletin 2022年第13期67卷 1335-1339,M0003页

作者： Jia Liu Wensi Zhang Kuang He Li Liu Chao Wang Yuanda Jiang Shijiao Ma Jiesheng Tian Ying Li Tongwei Zhang Lanxiang Tian Fei He Greig APaterson Yong Wei Yongxin Pan Wei Lin Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms Chinese Academy of SciencesBeijing 100029China Frontiers Science Center for Deep Ocean Multispheres and Earth System Key Lab of Submarine Geosciences and Prospecting Techniques(Ministry of Education)College of Marine GeosciencesOcean University of ChinaQingdao 266100China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Electronics and Information Technology for Space Systems National Space Science CenterChinese Academy of SciencesBeijing 100190China State Key Laboratories for Agro-biotechnology College of Biological SciencesChina Agricultural UniversityBeijing 100193China Department of Earth Ocean and Ecological SciencesUniversity of LiverpoolLiverpool L697ZEUK

地球临近空间指海平面之上20~100 km高度区域,具有高辐射、低温、干燥、低气压等极端条件,是一类典型的类火星环境.研究生命在临近空间的存活机制有助于深化对火星宜居性和生命探测的认识.本研究利用自主研发的临近空间天体生物学载荷... 详细信息

地球临近空间指海平面之上20~100 km高度区域,具有高辐射、低温、干燥、低气压等极端条件,是一类典型的类火星环境.研究生命在临近空间的存活机制有助于深化对火星宜居性和生命探测的认识.本研究利用自主研发的临近空间天体生物学载荷和飞行实验平台,将趋磁细菌Magnetospirillum gryphiswaldense MSR-1带入23 km高度区域开展生物暴露实验.结果发现合成磁小体的趋磁细菌经过7小时16分钟的暴露后仍有部分细胞存活,而不合成磁小体的菌株经过暴露后没有检测到存活细胞;临近空间暴露后存活的样品与实验室对照组相比,其磁小体的数量、尺寸和岩石磁学性质等均发生变化.这些结果表明细胞内的磁小体纳米颗粒有助于趋磁细菌抵御临近空间的高辐射等极端环境,为趋磁细菌的起源和早期演化、生命适应类火星极端环境的机制等提供了新认识.鉴于趋磁细菌具有在类火星环境中生存的潜力,这些感磁微生物可以作为天体生物学研究的重要生物类群.

关键词：天体生物学极端环境极端条件生命探测趋磁细菌磁小体临近空间宜居性

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Continuous and comprehensive atmospheric observations in Beijing:a station to understand the complex urban atmospheric environment

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Big Earth Data 2020年第3期4卷 295-321页

作者： Yongchun Liu Chao Yan Zemin Feng Feixue Zheng Xiaolong Fan Yusheng Zhang Chang Li Ying Zhou Zhuohui Lin Yishou Guo Ying Zhang Li Ma Wenshuo Zhou Zhikun Liu Lubna Dada Kaspar Dallenbach Jenni Kontkanen Runlong Cai Tommy Chan Biwu Chu Wei Du Lei Yao Yonghong Wang Jing Cai Juha Kangasluoma Tom Kokkonen Joni Kujansuu Anton Rusanen Chenjuan Deng Yueyun Fu Rujing Yin Xiaoxiao Li Yiqun Lu Yiliang Liu Chaofan Lian Dongsen Yang Weigang Wang Maofa Ge Yuesi Wang Douglas R.Worsnop Heikki Junninen Hong He Veli-Matti Kerminen Jun Zheng Lin Wang Jingkun Jiang Tuukka Petaja Federico Bianchi Markku Kulmala Aerosol and Haze Laboratory Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijingChina Institute for Atmospheric and Earth System Research/Physics Faculty of ScienceUniversity of HelsinkiHelsinkiFinland State Key Joint Laboratory of Environment Simulation and Pollution Control State Environmental Protection Key Laboratory of Sources and Control of Air Pollution ComplexSchool of EnvironmentTsinghua UniversityBeijingChina State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijingChina Department of Environmental Science&Engineering Fudan UniversityShanghaiChina State Key Laboratory for Structural Chemistry of Unstable and Stable Species Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijingChina Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Nanjing University of Information Science&TechnologyNanjingChina State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Aerodyne Research Inc. BillericaMassachusettsUSA Institute of Physics University of TartuTartuEstonia Joint International Research Laboratory of Atmospheric and Earth System Sciences School of Atmospheric SciencesNanjing UniversityNanjingChina

Due to profound impact on climate and human health,air quality has attracted attention from all levels of the civil *** key step in the provision of required tools for the society to tackle the complex air quality problem is to characterize it in a comprehensive manner with a long-term ***,we describe a continuous and comprehensive observation station and its accompanying state-ofthe-art instrumentation that was established to investigate the complex urban atmospheric environment in a rapidly developing Chinese *** station,located in downtown Beijing,aims to study air quality by identifying the major atmospheric pollutants and key processes determining their formation and loss mechanisms.A few hundreds of parameters are continuously measured with the state-of-the-art instruments,including trace gas concentrations,aerosol particle size distributions,and mass concentrations,covering aerosol particle chemical composition from molecules to micrometer-sized aerosol *** produced long-term,comprehensive big data with around 1�10^(11)bytes per *** this paper,we provide an overview on the facilities of the station,the instrumentation used,the workflow of continuous observations and examples of results from 2018 to 2019 and a basis for establishing a modern long-term,comprehensive atmospheric urban observation station in other megacities.

关键词： Continuous and comprehensive atmospheric observation air pollution complex photochemical smog haze new particle formation

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Optimal Scheduling Strategy of a Regional Integrated Energy system Considering Renewable Energy Uncertainty and Heat Network Transmission Characteristics

SSRN

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SSRN 2022年

作者： Chen, Haipeng Gao, Lin Zhang, Yongling Zhao, Chang Key Laboratory of Modern Power System Simulation and Control & Renewable Energy Technology Ministry of Education Northeast Electric Power University Jilin132012 China Department of Electrical Engineering Northeast Electric Power University Jilin132012 China Gongqing Institute of Science and Technology Gongqing City 332020 China National New Energy Group Jilin Jiangnan Thermal Power Limited Company Jilin132012 China

In order to overcome the curtailment of wind energy caused by "power determined by heat" of combined heat and power units, this study proposes an integrated demand response strategy and optimization method for heat-electric energy dispatching in a regional integrated energy system. Firstly, a scene analysis model based on Latin Hypercube Sampling (LHS) and Backward Reduction (BR) is constructed to analyze the probabilistic properties of wind power output in various scenes, and further provide a necessary reference for integrated energy scheduling. Secondly, the schedulable electrical power and thermal demand are evaluated with the consideration of the transmission characteristics of the heat supply network, then the integrated demand response of electric-thermal coordination is adopted to facilitate suppress the heat load fluctuation and wind power consumption. Finally, the optimal scheduling model of regional integrated energy system is established considering the source-load coordination, and the optimal output of each power unit is determined with the goal of minimizing overall cost during the scheduling period. The simulation results demonstrated that the proposed scheduling method reduces the operation cost of the integrated energy system and effectively promotes the wind energy consumption. Furthermore, it serves as a benchmark for the coordinated operation of wind turbines and power grids. © 2022, The Authors. All rights reserved.

关键词： Electric power utilization

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A location method for ground moving target with azimuth spectrum aliasing in Geosynchronous spaceborne-Airborne Bistatic multichannel SAR

A location method for ground moving target with azimuth spec...

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2019 IEEE International Conference on Signal, Information and Data Processing, ICSIDP 2019

作者： Zhang, Ying Xiong, Wei Dong, Xichao Hu, Cheng Liu, Chengxiang Sun, Yang Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing China School of Information and Electronics Beijing Institute of Technology Beijing China Key Laboratory of Electronic and Information Technology in Satellite Navigation Ministry of Education Beijing China

ISBN: (纸本)9781728123455

Geosynchronous spaceborne-Airborne Bistatic multichannel SAR (GEO-SABM SAR) maintains the fine temporal sampling and wide coverage characteristics of monostatic GEO SAR. But due to the PRF of GEO platform is very low, azimuth spectrum aliasing (ASA) will occur in GEO-SABM SAR which will make a moving target divided into several sub-targets. In this paper, a location method for ground moving target with ASA has given. From the simulation results, the moving target can be discriminated and located. © 2019 IEEE.

关键词： Synthetic aperture radar

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A Constructive Semi-global Differential Game Design Method for Multi-agent systems under Input Constraint and Collision Avoidance*

A Constructive Semi-global Differential Game Design Method f...

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Chinese Automation Congress (CAC)

作者： Xiongjun Wu Jialing Zhou Yuanlong Li Chunfang Chen Kai Li National Defense Key Laboratory of Science and Technology on Electromagnetic Scattering The 802 Institute of Shanghai Academy of Space Flight Technology The Eighth Academy of China Aerospace Science and Technology Corporation Shanghai China Key Laboratory of System Control and Information Processing Ministry of Education of China Shanghai Jiao Tong University Shanghai China School of Automation Nanjing University Science and Technology Nanjing The 802 Institute of Shanghai Academy of Space Flight Shanghai School of Automation Science and Electrical Engineering Beihang University Beijing

ISBN: (纸本)9781665426480

The constructive semi-global differential game concept is introduced into the multi-agent’s cooperative controller designing of typical autonomous unmanned systems subject to controller input constraint as well as the collision avoidance requirements simultaneously. The problem of driving each agent which is assume to subject to input constraint nonlinearity from the initial position to a desired one and at the same time avoiding collisions (referring to both static obstacles and other agents) is modeled and transformed into multi-agent’s collision avoidance problem. In view of the requirement that different agents working together might possibly have individual but conflicting purpose (such as in the multi-missile cooperative detection requiring slowly and continuing actions vs fast formation control scenario, and multi-agents’ fast arriving vs avoiding different kinds of obstacles). The differential game theory provided a mechanism or framework for investigating different kinds of problems in which several players seek to achieve individual purposes or goals, which might be competing rather than cooperation. In view of the input constraints, the problem is reduced as a semi-global differential game. Conditions are established to guarantee input constraints are satisfied, and mainly by using the Hamilton-Jacobi-Isaacs (HJI for short) PDIs and as well as ε-Nash equilibria. The semi-global property of the states are also guaranteed. It provides a description in terms of the invariant set for the overall differential game system under constraint controller input. Illustrative examples are carried out to verify the effectiveness of the method, and also the feasibility of the suggested control protocols.

关键词： Protocols Automation Design methodology Differential games Games Control systems Collision avoidance

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FCNet: A Convolutional Neural Network for Arbitrary-Length Exposure Estimation

arXiv

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arXiv 2022年

作者： Liang, Jin Yang, Yuchen Zhang, Anran Xu, Jun Li, Hui Zhen, Xiantong School of Statistics and Data Science Nankai University Tianjin300071 China School of Mathematics Science Nankai University Tianjin300071 China Guangdong University of Petrochemical Technology Guangdong Maoming China Key Laboratory of Advanced Technology of Near Space Information System Beihang University Beijing China Imaging Algorithm Research Department vivo Mobile Communication Co. Ltd. Shenzhen518101 China

The photographs captured by digital cameras usually suffer from over or under exposure problems. For image exposure enhancement, the tasks of Single-Exposure Correction (SEC) and Multi-Exposure Fusion (MEF) are widely studied in the image processing community. However, current SEC or MEF methods are developed under different motivations and thus ignore the internal correlation between SEC and MEF, making it difficult to process arbitrary-length sequences with improper exposures. Besides, the MEF methods usually fail at estimating the exposure of a sequence containing only under-exposed or over-exposed images. To alleviate these problems, in this paper, we develop a novel Fusion-Correction Network (FCNet) to tackle an arbitrary-length (including one) image sequence with improper exposures. This is achieved by fusing and correcting an image sequence Copyright © 2022, The Authors. All rights reserved.

关键词： Image enhancement

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