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Journal of Mountain Science 2024年第2期21卷 555-573页

作者： peng Hao qin Dahui wang Zegen zhang Menghan YANG Yanmei YONG Zhiwei School of Civil Engineering and Geomatics Southwest Petroleum UniversityChengdu 610500China School of Geoscience and technology Southwest Petroleum UniversityChengdu 610500China

In order to obtain more accurate precipitation data and better simulate the precipitation on the Tibetan Plateau,the simulation capability of 14 coupled Model Intercomparison Project Phase 6(CMIP6)models of historical precipitation(1982-2014)on the qinghai-Tibetan Plateau was evaluated in this *** indicate that all models exhibit an overestimation of precipitation through the analysis of the Taylor index,temporal and spatial statistical *** correct the overestimation,a fusion correction method combining the Backpropagation Neural Network correction(BP)and Quantum Mapping(QM)correction,named BQ method,was *** this method,the historical precipitation of each model was corrected in space and time,*** correction results were then analyzed in time,space,and analysis of variance(ANOVA)with those corrected by the BP and QM methods,***,the fusion correction method results for each model were compared with the Climatic Research Unit(CRU)data for significance analysis to obtain the trends of precipitation increase and decrease for each *** results show that the IPSL-CM6A-LR model is relatively good in simulating historical precipitation on the qinghai-Tibetan Plateau(R=0.7,RSME=0.15)among the uncorrected *** terms of time,the total precipitation corrected by the fusion method has the same interannual trend and the closest precipitation values to the CRU data;In terms of space,the annual average precipitation corrected by the fusion method has the smallest difference with the CRU data,and the total historical annual average precipitation is not significantly different from the CRU data,which is better than BP and ***,the correction effect of the fusion method on the historical precipitation of each model is better than that of the QM and BP *** precipitation in the central and northeastern parts of the plateau shows a significant increasing *** correlation coefficients between monthly

关键词： GCM CMIP6 Precipitation correction BP-QM fusion correction Spatio-temporal characteristics

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Vision Transformers with Hierarchical Attention

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Machine Intelligence Research 2024年第4期21卷 670-683页

作者： Yun liu Yu-huan Wu Guolei Sun Le zhang Ajad Chhatkuli Luc Van Gool Institute for Infocomm Research(I2R) A*STARSingapore 138632Singapore Institute of High Performance computing(IHPC) A*STARSingapore 138632Singapore computer Vision Lab ETH ZürichZürich 8092Switzerland School of Information and communication Engineering University of Electronic Science and Technology of China(UESTC)Chengdu 611731China

This paper tackles the high computational/space complexity associated with multi-head self-attention(MHSA)in vanilla vision *** this end,we propose hierarchical MHSA(H-MHSA),a novel approach that computes self-attention in a hierarchical ***,we first divide the input image into patches as commonly done,and each patch is viewed as a ***,the proposed H-MHSA learns token relationships within local patches,serving as local relationship ***,the small patches are merged into larger ones,and H-MHSA models the global dependencies for the small number of the merged *** last,the local and global attentive features are aggregated to obtain features with powerful representation *** we only calculate attention for a limited number of tokens at each step,the computational load is reduced ***,H-MHSA can efficiently model global relationships among tokens without sacrificing fine-grained *** the H-MHSA module incorporated,we build a family of hierarchical-attention-based transformer networks,namely *** demonstrate the superiority of HAT-Net in scene understanding,we conduct extensive experiments on fundamental vision tasks,including image classification,semantic segmentation,object detection and instance ***,HAT-Net provides a new perspective for vision *** and pretrained models are available at https://***/yun-liu/HAT-Net.

关键词： Vision transformer hierarchical attention global attention local attention scene understanding.

The occurrence characteristics of oil in shales matrix from organic geochemical screening data and pore structure properties:An experimental study Author links open overlay panel

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Petroleum Science 2024年第1期21卷 1-13页

作者： Zi-Zhi Lin Jun-Qian Li Shuang-Fang Lu qin-Hong Hu peng-Fei zhang Jun-Jie wang Qi Zhi Hong-Sheng huang Na Yin Yue wang Tian-chen Ge National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580ShandongChina School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Sanya Offshore Oil&Gas Research Institute Northeast Petroleum UniversitySanya 572025HainanChina college of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590ShandongChina

The occurrence characteristics of shale oil are of great significance to the movability of shale *** this study,the occurrence characteristics of oil in the shale matrix at Funing Formation shale in Subei Basin were quantitatively evaluated by organic geochemistry and microscopic pore structure characterization *** Multiple Isothermal Stages Pyrolysis(MIS)experiment results show that the content of total oil,adsorbed oil,and free oil in the shales are 3.15-11.25 mg/g,1.41-4.95 mg/g,and 1.74-6.51 mg/g,*** which the silicon-rich shale has the best *** relative content of free oil shows an increasing trend in pores with pore diameters greater than 3 *** the relative content of free oil reaches 100%,the pore size of silicon-rich shale is about 200 nm,while that of calcium-rich shale,clay-rich shale,and siliceous mixed shale is about 10 *** occurrence law of adsorbed oil is opposite to that of free oil,which indicates that shale oil will occur in the pores and fractures in a free state in a more extensive pore size range(>200 nm).This study also enables us to further understand the occurrence characteristics of shale oil under the interaction of occurrence state and occurrence space.

关键词： Shale oil Occurrence characteristics Sequential solvent extraction Low-temperature nitrogen adsorption Funing Formation Dongtai Depression

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Return to the Moon:New perspectives on lunar exploration

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Science Bulletin 2024年第13期69卷 2136-2148页

作者： Yangting Lin Wei Yang Hui zhang Hejiu Hui Sen Hu Long Xiao Jianzhong liu Zhiyong Xiao Zongyu Yue Jinhai zhang Yang liu Jing Yang Honglei Lin Aicheng zhang Dijun Guo Sheng Gou Lin Xu Yuyang He Xianguo zhang Liping qin Zongcheng Ling Xiongyao Li Aimin Du Huaiyu He peng zhang Jinbin Cao Xianhua Li Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory for Mineral Deposits Research and School of Earth Sciences and Engineering Nanjing UniversityNanjing 210023China State Key Laboratory of Geological Processes and Mineral Resources School of Earth SciencesChina University of GeosciencesWuhan 430074China Institute of Geochemistry Chinese Academy of SciencesGuiyang 550002China Planetary Environmental and Astrobiological Research Laboratory School of Atmospheric SciencesSun Yat-sen UniversityZhuhai 519082China National space Science Center Chinese Academy of SciencesBeijing 100190China Deep space Exploration Laboratory/CAS Key Laboratory of Crust-Mantle Materials and Environments University of Science and Technology of ChinaHefei 230026China Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China technology and Engineering Center for space Utilization Chinese Academy of SciencesBeijing 100094China School of space and Environment Beihang UniversityBeijing 100191China

Lunar exploration is deemed crucial for uncovering the origins of the Earth-Moon system and is the first step for advancing humanity’s exploration of deep *** the past decade,the Chinese Lunar Exploration Program(CLEP),also known as the Chang’e(CE)Project,has achieved remarkable *** has successfully developed and demonstrated the engineering capability required to reach and return from the lunar ***,the CE Project has made historic firsts with the landing and on-site exploration of the far side of the Moon,along with the collection of the youngest volcanic samples from the Procellarum KREEP *** achievements have significantly enhanced our understanding of lunar *** on this success,China has proposed an ambitious crewed lunar exploration strategy,aiming to return to the Moon for scientific exploration and *** plan encompasses two primary phases:the first crewed lunar landing and exploration,followed by a thousand-kilometer scale scientific expedition to construct a geological cross-section across the lunar *** the limitations of current lunar exploration efforts and China’s engineering and technical capabilities,this paper explores the benefits of crewed lunar exploration while leveraging synergies with robotic *** study refines fundamental lunar scientific questions that could lead to significant breakthroughs,considering the respective engineering and technological *** research lays a crucial foundation for defining the objectives of future lunar exploration,emphasizing the importance of crewed missions and offering insights into potential advancements in lunar science.

关键词： Crewed lunar exploration Water and volatiles composition and structure of lunar interior Volcanic activity and evolution of lunar mantle space weathering and radiation environments Exploration technology

Heterogeneous MXene-based films with graded electrical conductivity towards highly efficient EMI shielding and electrothermal heating

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Nano Research 2024年第8期17卷 7264-7274页

作者： Yu zhang Guangcheng zhang Zhonglei Ma Jianbin qin Xi Shen Department of Aeronautical and Aviation Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Shaanxi Key Laboratory of Macromolecular Science and technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Research Institute for Sports Science and technology The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

The increasing need for electromagnetic interference(EMI)shielding of electronics in cold environments such as those in aircraft,space exploration,and wearable heaters to avoid hazardous icing conditions or hypothermia requires the development of thin and lightweight EMI shielding materials preferably by absorbing rather than reflecting electromagnetic(EM)waves while also generating heat through energy-efficient electrothermal ***,it is challenging to achieve absorption-dominant EMI shielding and energy-efficient electrothermal heating simultaneously in a thin and lightweight ***,we develop a heterogeneous composite film comprising a porous multi-walled carbon nanotubes(MWCNTs)/bacterial cellulose(BC)film and an aligned MXene/Ag nanowires(NWs)backing via a sequential vacuum filtration *** porous film contains random conductive networks of MWCNTs with moderate conductivity while the aligned MXene sheets atop Ag NWs network affords high conductivity in the backing,giving rise to graded electrical conductivity for absorption-dominant EMI *** increasing Ag NW coverage leads to significantly increased electrical conductivity without increasing the EM wave reflection as well as the density and thickness of the film,yielding excellent specific EMI shielding effectiveness(>8500 dB/(g·cm^(2))),low driving voltage for energy-efficient electrothermal heating(163℃at 2.5 V),and fast response time(60 s)at a low areal density of 0.015 mg/cm^(2).combining EMI shielding and electrothermal heating,the heterogeneous film developed here are promising contenders for the protection of electronic equipment in low-temperature environment.

关键词： heterogenous composite film MXene electromagnetic interference(EMI)shielding thermal management

Multi-agent policy transfer via task relationship modeling

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Science China(Information Sciences) 2024年第8期67卷 102-114页

作者： Rongjun qin Feng cheN Tonghan wang Lei YUAN Xiaoran WU Yipeng KANG Zongzhang zhang Chongjie zhang Yang YU National Key Laboratory for Novel Software technology Nanjing University Polixir Technologies School of Engineering and Applied Sciences Harvard University Department of computer Science and technology Tsinghua University Institute for Interdisciplinary Information Sciences Tsinghua University

Team adaptation to new cooperative tasks is a hallmark of human intelligence, which has yet to be fully realized in learning agents. Previous studies on multi-agent transfer learning have accommodated teams of different sizes but heavily relied on the generalization ability of neural networks for adapting to unseen tasks. We posit that the relationship among tasks provides key information for policy *** utilize this relationship for efficient transfer by attempting to discover and exploit the knowledge among tasks from different teams, proposing to learn an effect-based task representation as a common latent space among tasks, and using it to build an alternatively fixed training scheme. Herein, we demonstrate that task representation can capture the relationship among teams and generalize to unseen tasks. Thus, the proposed method helps transfer the learned cooperation knowledge to new tasks after training on a few source ***, the learned transferred policies help solve tasks that are difficult to learn from scratch.

关键词： multi-agent reinforcement learning cooperative transfer learning task relationship modeling multi-agent policy reuse multi-agent multi-task learning

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Synergically regulated silver species and surface oxygen on manganese oxide for promoted activity of formaldehyde oxidation

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Journal of Environmental Sciences 2024年第4期138卷 709-718页

作者： Shuo Hu Jianghao zhang Xueyan chen Xiaoxiao qin Jinshui Yao Changbin zhang School of Materials Science&Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China State Key Joint Laboratory of Environment Simulation and Pollution control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Formaldehyde(HCHO)is a common indoor pollutant that is detrimental to human *** efficient removal has become an urgent demand to reduce the public health *** this work,Ag-MnO_(x)-based catalysts were prepared and activated under different atmosphere(i.e.,air,hydrogen(H_(2))and carbon monoxide(co))for efficient oxidation of *** catalyst activated with co(Ag/Mn-co)displayed the highest activity among the tested samples with 90% conversion at 100℃ under a gas space velocity of 75,000 mL/(g_(cat)·hr).complementary characterizations demonstrate that co reduction treatment resulted in synergically regulated content of surface oxygen on support to adsorb/activate HCHO and size of Ag particle to dissociate oxygen to oxidize the adsorbed *** contrast,other catalysts lack for either abundant surface oxygen species or metallic silver with the appropriate particle size,so that the integrate activity is limited by one specific reaction *** study contributes to elucidating the mechanisms regulating the oxidation activity of Ag-based catalysts.

关键词： HCHO oxidation Ag-MnO_(x)-based catalyst Activation condition Synergic regulation Surface oxygen Oxidized Ag

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Distributed Dynamic Load in Structural Dynamics by the Impulse-Based Force Estimation Algorithm

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computer Modeling in Engineering & Sciences 2024年第6期139卷 2865-2891页

作者： Yuantian qin Yucheng zhang Vadim V.Silberschmidt college of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing210016China Wolfson School of Mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughboroughLE113TUUK

This paper proposes a novel approach for identifying distributed dynamic loads in the time *** polynomial andmodal analysis,the load is transformed intomodal space for coefficient *** allows the distributed dynamic load with a two-dimensional form in terms of time and space to be simultaneously identified in the form of modal force,thereby achieving dimensionality *** Impulse-based Force Estimation Algorithm is proposed to identify dynamic loads in the time ***,the algorithm establishes a recursion scheme based on convolution integral,enabling it to identify loads with a long history and rapidly changing forms over ***,the algorithm introduces moving mean and polynomial fitting to detrend,enhancing its applicability in load *** aforementioned methodology successfully accomplishes the reconstruction of distributed,instead of centralized,dynamic loads on the continuum in the time domain by utilizing acceleration *** validate the effectiveness of the method,computational and experimental verification were conducted.

关键词： Distributed force estimation time domain deconvolution recursion

Frameworked electrolytes:Ionic transport behavior and high mobility for solid state batteries

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InfoMat 2024年第2期6卷 76-89页

作者： Jianguo Sun Hao Yuan Jing Yang Tuo wang Yulin Gao Qi Zhao Ximeng liu Haimei wang Yong-Wei zhang John wang Department of Materials Science and Engineering National University of SingaporeSingaporeSingapore Institute of High Performance computing(IHPC) Agency for ScienceTechnology and Research(A*STAR)SingaporeSingapore ST Engineering Advanced Material Engineering Pte.ltd. SingaporeSingapore National University of Singapore(Chongqing)Research Institute Chongqing Liang Jiang New AreaChongqingthe People's Republic of China Institute of Materials Research and Engineering(IMRE) Agency for ScienceTechnology and Research(A*STAR)SingaporeSingapore

All solid-state batteries(ASSBs)are the holy grails of rechargeable batteries,where extensive searches are ongoing in the pursuit of ideal solid-state ***,there is still a long way off to the satisfactorily high(enough)ionic conductivity,long-term stability and especially being able to form compatible interfaces with the solid ***,we have explored ionic transport behavior and high mobility in the sub-nano pore networks in the framework ***,the frameworked electrolyte behaves as a solid,and however in the(sub)-nano scales,the very limited number of solvent molecules in confinement makes them completely different from that in liquid *** from a liquid-electrolyte counterpart,the interactions between the mobile ions and surrounding molecules are subject to dramatic changes,leading to a high ionic conductivity at room temperature with a low activation ***+ions in the sub-nano cages of the network structure are highly mobile and diffuse rather independently,where the rate-limiting step of ions crossing cages is driven by the local concentration gradient and the electrostatic interactions between Li^(+)*** new class of frameworked electrolytes(FEs)with both high ionic conductivity and desirable interface with solid electrodes are demonstrated to work with Li-ion batteries,where the ASSB with LiFePO_(4)shows a highly stable electrochemical performance of over 450 cycles at 2℃ at room temperature,with an almost negligible capacity fade of 0.03‰ each *** addition,the FE shows outstanding flexibility and anti-flammability,which are among the key requirements of large-scale applications.

关键词： frameworked electrolyte macroscopically solid with 3D ionic channels in sub-nano-scales solid-state battery space confinement of Li ions