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Joint UAV trajectory and communication design with heterogeneous multi-agent reinforcement learning

Science China(Information Sciences) 2024年第3期67卷 225-245页

作者： Xuanhan ZHOU Jun XIONG Haitao ZHAO Xiaoran LIU Baoquan REN Xiaochen ZHANG Jibo wei Hao yin College of Electronic Science and Technology National University of Defense Technology Systems Engineering Institute Academy of Military Sciences PLA

Unmanned aerial vehicles(UAVs) are recognized as effective means for delivering emergency communication services when terrestrial infrastructures are unavailable. This paper investigates a multiUAV-assisted communication system, where we jointly optimize UAVs’ trajectories, user association, and ground users(GUs)’ transmit power to maximize a defined fairness-weighted throughput metric. Owing to the dynamic nature of UAVs, this problem has to be solved in real time. However, the problem’s non-convex and combinatorial attributes pose challenges for conventional optimization-based algorithms, particularly in scenarios without central controllers. To address this issue, we propose a multi-agent deep reinforcement learning(MADRL) approach to provide distributed and online solutions. In contrast to previous MADRLbased methods considering only UAV agents, we model UAVs and GUs as heterogeneous agents sharing a common objective. Specifically, UAVs are tasked with optimizing their trajectories, while GUs are responsible for selecting a UAV for association and determining a transmit power level. To learn policies for these heterogeneous agents, we design a heterogeneous coordinated QMIX(HC-QMIX) algorithm to train local Q-networks in a centralized manner. With these well-trained local Q-networks, UAVs and GUs can make individual decisions based on their local observations. Extensive simulation results demonstrate that the proposed algorithm outperforms state-of-the-art benchmarks in terms of total throughput and system fairness.

关键词： unmanned aerial vehicle (UAV) trajectory design resource allocation multi-agent deep reinforcement learning (MADRL) heterogeneous agents

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Remote copper-catalyzed enantioselective substitution of yne-thiophene carbonates

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Science China Chemistry 2024年第4期67卷 1175-1180页

作者： Hao-Dong Qian Xiang Li Tingrui yin wei-Feng Qian Chunhui Zhao Cuiju Zhu Hao Xu CCNU-uOttawa Joint Research Centre Key Laboratory of Pesticides&Chemical Biology of Ministry of EducationInternational Joint Research Center for Intelligent Biosensing Technology and HealthCollege of ChemistryCentral China Normal UniversityWuhan 430079China

Here,we describe a strategy for the copper-catalyzed asymmetric heteroarylation of yne-thiophene carbonates with indoles via remote *** key to the success of this strategy lies in the design of the alkynyl group at the ortho-position of the heterocycle thiophene,enabling the formation of a triarylmethane moiety via very remote ***,the concept of remote copper-catalyzed asymmetric transformation extends not only to yne-allylic esters but also to yne-aryl *** reaction readily provides a diverse array of chiral triarylmethanes with high efficiency,enantioselectivity,and excellent functional group ***,facile follow-up transformations underscore their potential utility in the synthesis of various enantioenriched building *** mechanistic studies support the plausibility of the remote substitution pathway.

关键词： remote substitution copper catalyst asymmetric catalysis triaryl methanes

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Pyridinic-N doping carbon layers coupled with tensile strain of FeNi alloy for activating water and urea oxidation

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Green Energy & Environment 2024年第4期9卷 684-694页

作者： Guangfu Qian wei Chen Jinli Chen Li Yong Gan Tianqi Yu Miaojing Pan Xiaoyan Zhuo Shibin yin Guangxi Key Laboratory of Electrochemical Energy Materials College of Chemistry and Chemical EngineeringState Key Laboratory of Processing for Non-Ferrous Metal and Featured MaterialsGuangxi University100 Daxue RoadNanning530004China Institute for Structure and Function and Department of Physics Chongqing UniversityChongqing400030China

Exploitation of oxygen evolution reaction(OER)and urea oxidation reaction(UOR)catalysts with high activity and stability at large current density is a major challenge for energy-saving H_(2) production in water ***,we use the pyridinic-N doping carbon layers coupled with tensile strain of FeNi alloy activated by NiFe_(2)O_(4)(FeNi/NiFe_(2)O_(4)@NC)for efficiently increasing the performance of water and urea *** to the tensile strain effect on FeNi/NiFe_(2)O_(4)@NC,it provides a favorable modulation on the electronic properties of the active center,thus enabling amazing OER(η_(100)=196 mV)and UOR(E_(10)=1.32 V)intrinsic ***,the carbon-coated layers can be used as armor to prevent FeNi alloy from being corroded by the electrolyte for enhancing the OER/UOR stability at large current density,showing high industrial *** work thus provides a simple way to prepare high-efficiency catalyst for activating water and urea oxidation.

关键词： Carbon-encapsulated Tensile strain Catalyst Oxygen evolution reaction Urea oxidation reaction

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Impact of atmospheric circulations on droughts and drought propagation over China

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Science China Earth Sciences 2024年第8期67卷 2633-2648页

作者： Ziye GU Lei GU Jiabo yin wei FANG Lihua XIONG Jun GUO Ziyue ZENG Jun XIA School of Civil and Hydraulic Engineering Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Water Resources Engineering and Management Wuhan 430072China Changjiang River Scientific Research Institute Wuhan 430010China

The GRACE satellite mission provides a new approach for monitoring,tracking,and assessing drought conditions by detecting changes in Earth's gravitational fields and inversing signals of terrestrial water storage *** studies of terrestrial water storage anomalies related droughts paid rare attention to the behind atmospheric physical mechanisms,nor quantified the risk propagation patterns between terrestrial water storage deficits and hydrological or agricultural *** this study,we first extract terrestrial water storage(TWS) droughts,hydrological droughts,and agricultural droughts by using multiple variables including TWS from the GRACE/GRACE-FO satellites,runoff and soil moisture from the ERA5-Land reanalysis *** then identify key atmospheric and oceanic oscillation indices affecting water deficits by employing machine learning *** characterize the joint distributions between drought duration and severity by using the Copula function and quantify the risk propagation of hydrological and agricultural droughts to TWS *** results show that:(1) From 2002 to 2021,there is a significant decrasing trend of TWS in China;the WPIO group atmospheric circulation indices(sea surface temperature index within the Western Pacific and Indian Ocean) contributes the most to ***,the sea surface temperature anomalies within the NINO 3.4 region as well as the Western Pacific Warm Pool area index show significantly positive correlation relationships with TWS in southern China;(2) The northwestern China,the Yangtze River basin,and the downstream of the Pearl River basin are the hotspots of TWS ***,the hotspots of hydrological droughts locate in northwestern China and the hotspots of agricultural droughts locate in South China and eastern Tibetan Plateau;(3) The elastic coefficients of hydrological droughts propagating to TWS droughts are higher than those of agricultural droughts,indicating that the TWS droughts

关键词： GRACE satellites Drought Drought propagation Atmospheric circulation Copula function

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Towards Domain-agnostic Depth Completion

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Machine Intelligence Research 2024年第4期21卷 652-669页

作者： Guangkai Xu wei yin Jianming Zhang Oliver Wang Simon Niklaus Simon Chen Jia-Wang Bian Zhejiang University Hangzhou 310058China DaJiang Technology Shenzhen 518057China Adobe Research California 95110USA University of Oxford Oxford OX12JDUK

Existing depth completion methods are often targeted at a specific sparse depth type and generalize poorly across task *** present a method to complete sparse/semi-dense,noisy,and potentially low-resolution depth maps obtained by various range sensors,including those in modern mobile phones,or by multi-view reconstruction *** method leverages a data-driven prior in the form of a single image depth prediction network trained on large-scale datasets,the output of which is used as an input to our *** propose an effective training scheme where we simulate various sparsity patterns in typical task *** addition,we design two new benchmarks to evaluate the generalizability and robustness of depth completion *** simple method shows superior cross-domain generalization ability against state-of-the-art depth completion methods,introducing a practical solution to highqualitydepthcapture onamobile device.

关键词： Monocular depth estimation depth completion zero-shot generalization scene reconstruction neural network.

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Electrohydrodynamic printing for high resolution patterning of flexible electronics toward industrial applications

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InfoMat 2024年第2期6卷 28-56页

作者： Zhouping yin Dazhi Wang Yunlong Guo Zhiyuan Zhao Liqiang Li wei Chen Yongqing Duan State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhanthe People's Republic of China Optics Valley Laboratory Wuhanthe People's Republic of China Key Laboratory for Micro/Nano Technology and System of Liaoning Province Dalian University of TechnologyDalianthe People's Republic of China Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijingthe People's Republic of China Institute of Molecular Aggregation Sciences Tianjin UniversityTianjinthe People's Republic of China

Electrohydrodynamic(EHD)printing technique,which deposits micro/nanostructures through high electric force,has recently attracted significant research interest owing to their fascinating characteristics in high resolution(<1μm),wide material applicability(ink viscosity 1–10000 cps),tunable printing modes(electrospray,electrospinning,and EHD jet printing),and compatibility with flexible/wearable *** the laboratory level of the EHD printed electronics'resolution and efficiency is gradually approaching the commercial application level,an urgent need for developing EHD technique from laboratory into industrialization have been put ***,we first discuss the EHD printing technique,including the ink design,droplet formation,and key technologies for promoting printing efficiency/*** we summarize the recent progress of EHD printing in fabrication of displays,organic field-effect transistors(OFETs),transparent electrodes,and sensors and ***,a brief summary and the outlook for future research effort are presented.

关键词： display electrohydrodynamic printing flexible electronics organic field-effect transistor printhead

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Tuning the membrane rejection behavior by surface wettability engineering for an effective water-in-oil emulsion separation

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Chinese Chemical Letters 2024年第6期35卷 480-485页

作者： Yan Zou yin-Shuang Hu Deng-Hui Tian hong Wu Xiaoshu Lv Guangming Jiang Yu-Xi Huang Engineering Research Center for Waste Oil Recovery Technology and Equipment Ministry of EducationChongqing Technology and Business UniversityChongqing 400067China School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology(Sun Yat-sen University) Guangzhou 510275China

Membrane-based separation is a promising technology to eliminate water impurities from the oil ***,it remains a great challenge to separate water from highly emulsified viscous oil owing to the high stability of the water droplets in *** we report a surface wettability engineering on an alumina ceramic membrane to achieve an efficient separation of a water-in-oil(W/O)*** with different carbon chain lengths and fluorinated status were introduced to endow the alumina membrane with different surface *** all the modified membranes exhibited excellent separation of the W/O without Span 80(surfactant),the one with amphiphobic wettability and lowest surface energy failed to separate the Span 80 stabilized W/*** presence of Span 80 reduced the interfacial tension of water droplets,making them easier to deform and penetrate the modified membrane with the lowest surface *** reveals that engineering proper surface wettability is the key to separating the oil and water ***,the modified membranes maintained decent separation performance and stability under long-term run separation of the emulsified W/O.

关键词： Water-in-oil emulsion Ceramic membrane Membrane separation Surface wettability

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Juvenile cardiomyopathy with dystrophin deficiency

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Genes & Diseases 2024年第3期11卷 30-33页

作者： Yuhui Luo Qinglan Shu Yi Wang Min Gu Hao Zhang Siqi hong Rui Wang Lixue yin Department of Cardiology Chongqing General HospitalChongqing 401147China Department of Cardiovascular Ultrasound and Noninvasive Cardiology Sichuan Provincial People's HospitalUniversity of Electronic Science and Technology of China(UESTC)ChengduSichuan 610072China Department of RadiologyChongqing General HospitalChongqing 401147China Department of Neurology Children's Hospital of Chongqing Medical UniversityChongqing 400014China School of Medicine Zunyi Medical UniversityZunyiGuizhou 563000China

Pseudohypertrophic muscular dystrophy is a lethal X-linked recessive neuromuscular disorder caused by mutations in the dystrophin *** gene encodes a cytoskeletal protein that is extensively expressed in muscle cells and that enables the strength,stability,and functionality of *** dystrophy can be grouped into two different categories based on the mutational rate and clinical severity,Duchenne muscular dystrophy(DMD)and Becker muscular dystrophy(BMD).DMD is the most common and the more severe type of *** patients usually become wheelchair-bound by the age of 12 years and die in their late teens to early twenties.^(1)In contrast,BMD is relatively less severe and the patients can potentially have alonger lifeexpectancy.

关键词： dystrophin dystrophy Becker

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Transcriptional regulation of MdPIN7 by MdARF19 during gravityinduced formation of adventitious root GSA in self-rooted apple stock

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Horticultural Plant Journal 2024年第5期10卷 1073-1084页

作者： Zenghui Wang Xuemei Yang Linyue Hu wei Liu Lijuan Feng Xiang Shen Yanlei yin Jialin Li Shandong Institute of Pomology Tai'anShandong 271000China School of Biological Science and Technology University of JinanJinanShandong 250022China State Key Laboratory of Crop Biology Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(Huanghuai Region)Ministry of AgricultureCollege of Horticulture Science and EngineeringShandong Agricultural UniversityTai'anShandong 271018China

Self-rooted apple stock is widely used for apple ***,the shallowness of the adventitious roots in self-rooted apple stock leads to poor performance in the barren orchards of *** is because of the considerable difference in the development of a gravitropic set-point angle(GSA)between self-rooted apple stock and seedling ***,it is crucial to study the molecular mechanism of adventitious root GSA in self-rooted apple stock for breeding self-rooted and deep-rooted apple rootstock *** apple auxin response factor MdARF19 functioned to establish the adventitious root GSA of self-rooted apple stock in response to gravity and auxin ***19 bound directly to the MdPIN7 promoter,activating its transcriptional expression and thus regulating the formation of the adventitious root GSA in 12-2 self-rooted apple ***,MdARF19 influenced the expression of auxin efflux carriers(MdPIN3 and MdPIN10)and the establishment of adventitious root GSA of self-rooted apple stock in response to gravity signals by direct activation of *** findings provide new information on the transcriptional regulation of MdPIN7 by auxin response factor MdARF19 in the regulation of the adventitious root GSA of self-rooted apple stock in response to gravity and auxin signals.

关键词： Apple Self-rooted stock Gravity MdARF19 MdPIN7 Gravitropic set-point angle Transcriptional regulation

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Four New Terpyridine Complexes Based Polyoxometalates with[W_(10)O_(32)]^(4-) Anions as High-Efficiency Dual-Site Catalysis for Thioether Oxidation Reaction

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Chinese Journal of Chemistry 2024年第6期42卷 592-598页

作者： yin Zhang wei-Dong Yu Fang-Qian Wang Xiangnan Wang Jiawan Zhou Chao Liu Jun Yan Junior Education Department Changsha Normal UniversityChangshaHunan410100 China School of Science Hunan University of Technology and BusinessChangshaHunan410000 China College of Chemistry and Chemical Engineering Central South UniversityChangshaHunan410000 China

Polyoxometalates modified with complex cations have attracted increasing attention because of the fascinating properties and the controllable *** adjusting the synthesis conditions,four new terpyridine complexes based hybrid POMs,[(TPY-H)CuCl]_(4)[W_(10)O_(32)]·2DMF·2H_(2)O(1),[(TPY-H)Cu(DMSO)(H_(2)O)]_(2)[W_(10)O_(32)]·2H_(2)O(2),[(TPY-H)_(2)Cu]_(2)[W_(10)O_(32)]·6DMSO·8H_(2)O(3) and[(TPY-Br)CuCl(DMSO)(H_(2)O)]_(2)[(TPY-Br)CuCl]_(2)[W_(10)O_(32)]·2DMSO·4H_(2)O(4),were prepared by using‘one-pot’***-crystal X-ray diffraction analyses,infrared radiation,etc.,revealed the structural composition of compounds 1—4,which indicates that synthesis conditions have a directional regulatory effect on the compounds *** oxidation catalytic reactions show 1—4 have good catalytic activities,and powder X-ray diffraction and thermogravimetry analysis show 1—4 have superduper catalytic ***,4 has better catalytic activity because of the different structure of terpyridine ***,a possible mechanism of dual-site catalysis by both cations and anions is proposed.

关键词： Polyoxometalates Terpyridine complexes Thioether oxidation Dual-site catalysis Clusters

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