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For LEO Satellite Networks: Intelligent Interference Sensing and Signal Reconstruction Based on Blind Separation Technology

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China Communications 2024年第2期21卷 85-95页

作者： Chengjie li lidong Zhu zhen Zhang The Key Laboratory for Computer Systems of State Ethnic Affairs Commission School of Computer Science and Technology(Southwest Minzu University)Chengdu 610000China National Key Laboratory of Science and Technology on Communications(University of Electronic Science and Technology of China) Chengdu 610000China College of Computer Science(Sichuan University) Chengdu 610000China

In LEO satellite communication networks,the number of satellites has increased sharply, the relative velocity of satellites is very fast, then electronic signal aliasing occurs from time to time. Those aliasing signals make the receiving ability of the signal receiver worse, the signal processing ability weaker,and the anti-interference ability of the communication system lower. Aiming at the above problems, to save communication resources and improve communication efficiency, and considering the irregularity of interference signals, the underdetermined blind separation technology can effectively deal with the problem of interference sensing and signal reconstruction in this scenario. In order to improve the stability of source signal separation and the security of information transmission, a greedy optimization algorithm can be executed. At the same time, to improve network information transmission efficiency and prevent algorithms from getting trapped in local optima, delete low-energy points during each iteration process. Ultimately, simulation experiments validate that the algorithm presented in this paper enhances both the transmission efficiency of the network transmission system and the security of the communication system, achieving the process of interference sensing and signal reconstruction in the LEO satellite communication system.

关键词： blind source separation greedy optimization algorithm interference sensing LEO satellite communication networks signal reconstruction

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For Mega-Constellations: Edge Computing and Safety Management Based on Blockchain Technology

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China Communications 2024年第2期21卷 59-73页

作者： zhen Zhang Bing Guo Chengjie li College of Computer Science Sichuan UniversityChengdu 610064China The Key Laboratory for Computer Systems of State Ethnic Affairs Commission School of Computer Science and TechnologySouthwest Minzu UniversityChengdu 610225China National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of ChinaChengdu 611731China

In mega-constellation Communication Systems, efficient routing algorithms and data transmission technologies are employed to ensure fast and reliable data transfer. However, the limited computational resources of satellites necessitate the use of edge computing to enhance secure *** edge computing reduces the burden on cloud computing, it introduces security and reliability challenges in open satellite communication channels. To address these challenges, we propose a blockchain architecture specifically designed for edge computing in mega-constellation communication systems. This architecture narrows down the consensus scope of the blockchain to meet the requirements of edge computing while ensuring comprehensive log storage across the network. Additionally, we introduce a reputation management mechanism for nodes within the blockchain, evaluating their trustworthiness, workload, and efficiency. Nodes with higher reputation scores are selected to participate in tasks and are appropriately incentivized. Simulation results demonstrate that our approach achieves a task result reliability of 95% while improving computational speed.

关键词： blockchain consensus mechanism edge computing mega-constellation reputation management

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Geographical Information System-Based Assessment of Ecological Security in Changbai Mountain Region

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Journal of Mountain Science 2014年第1期11卷 86-97页

作者： LU Xing-chang ZHANG Ji-quan li xiao-zhen School of Environment Northeast Normal University College of Geo-exploration Science & Technology Jilin University Anyang City Bureau of Agriculture

Ecological security defined as the creation of a condition where the physical surroundings of a community provide for the needs of its inhabitants without diminishing its natural stock,which is important for regional security and social *** recent years,land use patterns in the Changbai Mountain region have changed significantly with intensive human activities,and consequently led to increasing problems in regional ecological *** on the Pressure-State-Impact-Response(PSIR) model and the mathematical method of catastrophe progression supported by geographical information system(GIS),the ecological security situation of the study area under land use and cover change(LUCC) was *** results indicated that the ecological security in Changbai Mountain region varied nonlinearly,which got better from 1990 to 2000 but became worse from 2000 to 2007,the ecological security levels in Changbai Mountain region were mainly medium and medium to low during the past 17 years,with higher values of Ecological Security Index(ESI) in the central region and lower values in the east and west,the ecological security situation was more serious in the settlements and river valleys,where the LUCC was most remarkable.

关键词： Ecological security Pressure-State-Impact-Response Land use and cover change Geographical Information System(GIS) Catastrophe progression Changbai Mountain

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SAC-Based Computation Offloading for Reconfigurable Intelligent Surface-Aided Mobile Edge Networks

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China Communications 2024年第6期21卷 261-270页

作者： li Bin Qian zhen Fei Zesong School of Computer Science Nanjing University of Information Science&TechnologyNanjing 210044China Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology(CICAEET) Nanjing University of Information Science&TechnologyNanjing 210044 School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

In this paper,we concentrate on a reconfigurable intelligent surface(RIS)-aided mobile edge computing(MEC)system to improve the offload efficiency with moving user equipments(UEs).We aim to minimize the energy consumption of all UEs by jointly optimizing the discrete phase shift of RIS,UEs’transmitting power,computing resources allocation,and the UEs’task offloading strategies for local computing and *** formulated problem is a sequential decision making across multiple coherent time ***,the mobility of UEs brings uncertainties into the decision-making *** cope with this challenging problem,the deep reinforcement learning-based Soft Actor-Critic(SAC)algorithm is first proposed to effectively optimize the discrete phase of RIS and the UEs’task offloading ***,the transmitting power and computing resource allocation can be determined based on the *** results demonstrate that the proposed algorithm can be trained more stably and perform approximately 14%lower than the deep deterministic policy gradient benchmark in terms of energy consumption.

关键词： MEC RIS soft actor-critic user mobility

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Molecular Chain Flexibility and Dielectric Loss at High-Frequency:Impact of Ester Bond Arrangement in Poly(ester imide)s

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Chinese Journal of Polymer Science 2024年第8期42卷 1122-1133页

作者： Ya-Dong li Hong li Lu-Kun Feng Feng Bao Ming-liang Wang Cai-zhen Zhu Zhao-Hui zheng xiao-Bin Ding Jian Xu Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100081China Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China

The evolution of high-frequency communication has accentuated the significance of controlling dielectric properties in polymer ***,it has been theorized that rigid molecular chains lead to lower dielectric ***,the validity of this proposition at high frequencies remains *** scrutinize the correlation between chain flexibility and dielectric properties,we synthesized six poly(ester imide)s(PEIs)with systematically varied molecular chain flexibilities by modifying the ester's substitution on the aromatic *** introduction of ester bonds bestowed all PEI films with a low dielectric dissipation factor(D_(f)),ranging from 0.0021 to 0.0038 at 10 GHz in dry *** dry D_(f)displayed a pattern consistent with volume polarizability(P/V).Unexpectedly,PI-mmm-T,featu ring the most flexible molecular chain,exhibited the lowest dielectric loss under both dry(0.0021@10 GHz)and hygroscopic(0.0029@10 GHz)***,the observed increase in D_(f)after humidity absorption suggests that the high dielectric loss of PEI in applications may be attributed to its hygroscopic *** simulations and characterization of the aggregation structure revealed that the smaller cavities within flexible molecular chains,after close stacking,impede the entry of water *** sacrificing high-temperature resistance,the precursor exhibited enhanced solubility properties and could be processed into high-quality *** research unveils new insights into the relationship between flexibility and highfrequency dielectric loss,offering innovative perspectives on synthesizing aromatic polymers with exceptional dielectric properties.

关键词： 5G communications Poly(ester imide)s Molecular chain flexibility Dielectric properties Humidity absorption

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Decentralized Optimal Control and Stabilization of Interconnected Systems With Asymmetric Information

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 698-707页

作者： Na Wang xiao liang Hongdan li xiao Lu the College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266000China the School of Automation and Electrical Engineering Linyi UniversityLinyi 276000China the College of Energy Storage Technology Shandong University of Science and TechnologyQingdao 266000China

The paper addresses the decentralized optimal control and stabilization problems for interconnected systems subject to asymmetric *** with previous work,a closed-loop optimal solution to the control problem and sufficient and necessary conditions for the stabilization problem of the interconnected systems are given for the first *** main challenge lies in three aspects:Firstly,the asymmetric information results in coupling between control and estimation and failure of the separation ***,two extra unknown variables are generated by asymmetric information(different information filtration)when solving forward-backward stochastic difference ***,the existence of additive noise makes the study of mean-square boundedness an *** adopted technique is proving and assuming the linear form of controllers and establishing the equivalence between the two systems with and without additive noise.A dual-motor parallel drive system is presented to demonstrate the validity of the proposed algorithm.

关键词： Asymmetric information decentralized control forwardbackward stochastic difference equations interconnected system stalibization

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GreenPhos,a universal method for in-depth measurement of plant phosphoproteomes with high quantitative reproducibility

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Molecular Plant 2024年第1期17卷 199-213页

作者： xiaoxiao Duan Yuanya Zhang Xiahe Huang xiao Ma Hui Gao Yan Wang zhen xiao Chengcheng Huang Zhongshu Wang Bolong li Wenqiang Yang Yingchun Wang State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBejing 100101China University of Chinese Academy of Sciences Bejing 100049China Key Laboratory of Photobiology Instute of BotanyChinese Academy of SciencesBejing 100093China

Protein phosphorylation regulates a variety of important cellular and physiological processes in ***-depth profiling of plant phosphoproteomes has been more technically challenging than that of animal *** is largely due to the need to improve protein extraction efficiency from plant cells,which have a dense cell wall,and to minimize sample loss resulting from the stringent sample clean-up steps required for the removal of a large amount of biomolecules interfering with phosphopeptide purification and mass spectrometry *** this end,we developed a method with a streamlined workflow for highly efficient purification of phosphopeptides from tissues of various green organisms including Arabidopsis,rice,tomato,and Chlamydomonas reinhardtii,enabling in-depth identification with high quantitative reproducibility of about 11000 phosphosites,the greatest depth achieved so far with single liquid chromatography-mass spectrometry(LC-MS)runs operated in a data-dependent acquisition(DDA)*** mainstay features of the method are the minimal sample loss achieved through elimination of sample clean-up before protease digestion and of desalting before phosphopeptide enrichment and hence the dramatic increases of time-and *** method,named GreenPhos,combined with single-shot LC-MS,enabled in-depth quantitative identification of Arabidopsis phosphoproteins,including differentially phosphorylated spliceosomal proteins,at multiple time points during salt stress and a number of kinase substrate *** is expected to serve as a universal method for purification of plant phosphopeptides,which,if samples are further fractionated and analyzed by multiple LC-MS runs,could enable measurement of plant phosphoproteomes with an unprecedented depth using a given mass spectrometry technology.

关键词： plant phosphoproteomics phosphopeptides LC–MS Arabidopsis salt stress

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Progress and challenges of electrolyte modulation in aqueous zinc-ion batteries

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Rare Metals 2024年第7期43卷 2940-2967页

作者： Qi-Hang Yang Lu-Fei Wang xiao-Yu Wang Meng-Meng zhen Tianjin Key Laboratory of Clean Energy and Pollution Control School of Energy and Environmental EngineeringHebei University of TechnologyTianjin 300071China

As a new type of green battery system,aqueous zinc-ion batteries(AZIBs)have gradually become a research hotspot due to their low cost,high safety,excellent stability,high theoretical capacity(820 mAh·g^(-1))of zinc anode,and low redox potential(-0.76 V *** hydrogen electrode(SHE)).AZIBs have been expected to be an alternative to lithium-ion batteries for large-scale commercial energy storage ***,they are facing thorny issues such as degradation of cycling performance,zinc dendrites,and side *** the same time,these problems cause short cycling life of batteries,thus severely limiting their commercial *** recent years,many more researches have been conducted on the modification of anode and cathode materials of AZIBs,but there is a lack of in-depth discussion on the characteristics and mechanism of electrolyte *** this review,we will make a systematic summary of the current problems with two electrodes in AZIBs,as well as the types and functions of electrolyte ***,we further systematically describe the modulation mechanism of electrolyte additives in the performance of the cathode and *** prospects and development directions of additive modulation strategies for AZIBs electrolytes are prospected.

关键词： Electrolyte additives Aqueous zinc-ion batteries Zinc anode protection Cathode chemistry

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Effects of microplastic polystyrene,simulated acid rain and arbuscular mycorrhizal fungi on Trifolium repens growth and soil microbial community composition

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Pedosphere 2024年第2期34卷 424-437页

作者： Wanlin li Yan xiao College of Agro-grassland Science Nanjing Agricultural UniversityNanjing 210095China

Microplastic pollution is a global and ubiquitous environmental problem in the oceans as well as in the terrestrial *** examined the fate of microplastic polystyrene(MPS)beads in experimental soil in the presence and absence of symbiotic arbuscular mycorrhizal fungi(AMF)and simulated acid rain(SAR)to determine whether the combinations of these three factors altered the growth of white clover Trifolium *** found that MPS,SAR,or AMF added singly to soil did not alter *** growth or *** contrast,MPS and AMF together significantly reduced shoot biomass,while SAR and MPS together significantly reduced soil available phosphorus independent of AMF *** polystyrene,AMF,and SAR together significantly reduced soil NO_(3)^(-)-*** mycorrhizal fungi added singly also enriched the beneficial soil bacteria(genus Solirubrobacter),while MPS combined with AMF significantly enriched the potential plant pathogenic fungus *** mycorrhizal fungi inoculation with MPS increased the abundance of soil hydrocarbon degraders independent of the presence of *** addition,the abundance of soil nitrate reducers was increased by MPS,especially in the presence of AMF and ***,SAR alone increased the abundance of soil pathogens within the fungal community including antibiotic *** findings indicate that the coexistence of MPS,SAR,and AMF may exacerbate the adverse effects of MPS on soil and plant health.

关键词： acid deposition arbuscular mycorrhizal fungi symbiosis hydrocarbon degradation microbial alpha diversity microplastic pollution pathogen

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Two new glycosides from the seeds of Cassia obtusifolia

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Chinese Chemical Letters 2009年第9期20卷 1097-1099页

作者： Cun Zhang Gui liu li Yong Qing xiao li li zhen Pang Institute of Traditional Chinese Materia Madica Chinese Academy of Chinese Medical Sciences Beijing 100700 China

Two new glycosides, nor-rubrofusadn-6-O-β-D-（6＇-O-acetyl）glucopyranoside （1） and 1-desmethylaurantio-obtusin-2-O-β-D- glucopyranoside （2） were isolated from the seeds of Cassia obtusifolia and their structures were established by chemical and spectral evidences. 2009 Yong Qing xiao. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Cassia obtusifolia Nor-rubrofusarin-6-O-β-D-(6'-O-acetyl)glucopyranoside 1-Desmethylaurantio-obtusin-2-O-β-D-glucopyranoside

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