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Quantitatively determine the dominant driving factors of the spatial–temporal changes of vegetation NPP in the Hengduan Mountain area during 2000-2015

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Journal of Mountain Science 2021年第2期18卷 427-445页

作者： CHEN Shu-ting GUO Bing ZHANG Rui ZANG wen-qian WEI Cui-xia WU Hong-wei YANG Xiao ZHEN Xiao-yan li Xing ZHANG Da-fu HAN Bao-min ZHANG Hai-ling School of Civil Architectural Engineering Shandong University of TechnologyZibo 255000China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Land use Ministry of Natural ResourcesChina Land Survey and Planning InstituteBeijing 100035China Key Laboratory for Digital Land and Resources of Jiangxi Province East China University of TechnologyNanchang 330013China Key Laboratory of National Geographic Census and Monitoring Ministry of Natural ResourcesWuhan 430079China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100101China Key Laboratory of UrbanLand Resources Monitoring and Simulation Ministry of Natural ResourcesShenzhen 518000China Key Laboratory of Meteorology and Ecological Environment of Hebei Province Shijiazhuang 050021China Land Satellite Remote Sensing Application Center Ministry of Natural ResourcesBeijing 100048China College of Geological Engineering and Geomatics Chang'an UniversityXi'an 710054China

The Hengduan mountain area,located in the upper reaches of the Yangtze River of China,is an important ecological barrier that significantly impacts the climate and ecological environment of the surrounding region and western China as a *** paper introduces the gravity center model used to analyze the spatial-temporal variation patterns of vegetation Net Primary Productivity(NPP)from 2000 to 2015,which were determined by the use of MOD17 A3 NPP ***,the dominant driving factors of the spatial–temporal changes of vegetation NPP of the Hengduan Mountain area were quantitatively determined with a geographical detector over *** results revealed that:(1)From 2000 to 2015,there was an increasing trend of vegetation NPP in the Hengduan mountain *** the whole study region,the vegetation NPP with a mean value of 611.37 gC·m^(-2)·a^(-1) indicated a decreasing trend from southeast to northwest in terms of spatial distribution.(2)The gravity centers of vegetation NPP in 2000-2015 were mainly concentrated in Zhongdian *** the study period,the gravity center of vegetation NPP moved northward,which indicated that the increment and increasing rate of vegetation NPP in the northern parts were greater than that of the southern areas.(3)The vegetation NPP showed a moderately positive correlation with temperature,accumulated temperature(>10℃),and sunshine,while there was an overall negative relationship between NPP and precipitation.(4)The dominant factors and interactive dominant factors changed in different subregions over different segments of the study *** dominant factors of most sub-regions in Hengduan mountain were natural factors,and the climate change factors played an increasingly greater role over the 16 years of the study period.

关键词： Vegetation NPP Spatial-temporal distribution Driving factors Geographic detector Land use change

A Granularity-Aware Parallel Aggregation Method for Data Streams

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 133-137页

作者： WANG Yong-li XU Hong-bing XU li-zhen qian Jiang-bo liU Xue-jun Department of Computer Science and Engineering Southeast University Nanjing 210096 Jiangsu China

This paper focuses on the parallel aggregation processing of data streams based on the shared-nothing architecture. A novel granularity-aware parallel aggregating model is proposed. It employs parallel sampling and linear regression to describe the characteristics of the data quantity in the query window in order to determine the partition granularity of tuples, and utilizes equal depth histogram to implement partitio ning. This method can avoid data skew and reduce communi cation cost. The experiment results on both synthetic data and actual data prove that the proposed method is efficient, practical and suitable for time-varying data streams processing.

关键词： data streams parallel processing linear regression aggregation data skew

Sampling-efficient path planning and improved actor-critic-based obstacle avoidance for autonomous robots

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Science China(Information Sciences) 2024年第5期67卷 197-214页

作者： Yefeng YANG Tao HUANG Tianqi WANG wenyu YANG Han CHEN Boyang li Chih-yung wen Department of Aeronautical and Aviation Engineering The Hong Kong Polytechnic University Center for Control Theory and Guidance Technology Harbin Institute of Technology School of Engineering The University of Newcastle Research Center for Unmanned Autonomous Systems The Hong Kong Polytechnic University

Autonomous robots have garnered extensive utilization in diverse fields. Among the critical concerns for autonomous systems, path planning holds paramount importance. Notwithstanding considerable efforts in its development over the years, path planning for autonomous systems continues to grapple with challenges related to low planning efficiency and inadequate obstacle avoidance response in a timely *** study proposes a novel and systematic solution to the path planning problem within intricate office buildings. The solution consists of a global planner and a local planner. To handle the global planning aspect, an adaptive clustering-based dynamic programming rapidly exploring random tree(ACDP-RRT) algorithm is proposed. ACDP-RRT effectively identifies obstacles on the map by leveraging geometric *** obstacles are then represented as a collection of sequentially arranged convex polygons, optimizing the sampling region and significantly enhancing sampling efficiency. For local planning, a network decoupling actor-critic(ND-AC) algorithm is employed. The proposed ND-AC simplifies the local planner design process by integrating planning and control loops into a neural network(NN) trained via an end-to-end model-free deep reinforcement learning(DRL) framework. Moreover, the adoption of network decoupling(ND) techniques leads to an improved obstacle avoidance success rate when compared to conventional actor-critic(AC)-based methods. Extensive simulations and experiments are conducted to demonstrate the effectiveness and robustness of the proposed approach.

关键词： rapidly exploring random tree (RRT) adaptive clustering network decoupling actor critic (AC) path planning

Multiscale observation of li plating for lithium-ion batteries

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Rare Metals 2021年第11期40卷 3038-3048页

作者： Xin-Lei Gao Xin-Hua liu wen-Long Xie li-Sheng Zhang Shi-Chun Yang School of Transportation Science and Engineering Beihang UniversityBeijing 100191China

As the most hazardous side reaction,li plating poses high risks of undermining electrochemical performance of li-ion batteries by accelerating *** some extreme abuse conditions,li plating can even jeopardize safety performance and induce catastrophic results like thermal ***,multiscale observation of li plating is of great significance for understanding the internal mechanisms and early detection of li *** this mini-review,the recent progress of formation mechanisms of plated metallic lithium was ***,the in situ and ex situ observation methods of macroscopic,microscopic and atomic level were *** electrode provides a promising tool for real-time monitoring of anode potential,which is the critical factor of li plating,showing great potentials in cloudbased battery management ***,some perspectives for future researches on li plating observation and corresponding utilizations in developing li plating free control strategies were proposed.

关键词： lithium-ion battery li plating Multiscale observation Reference electrodes

Synthesis of oleanolic disaccharide derivatives

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Chinese Chemical Letters 2012年第4期23卷 403-406页

作者： Shu Chen Pei Jian Bo Wu Fan Lei Shan qian li Hai Yong Wu Key Laboratory of Drug Targeting and Drug Delivery System of the Education Ministry Department of Medicinal ChemistryWest China School of PharmacySichuan UniversityChengdu 610041China Bioengineering College Xihua UniversityChengdu 610039China

Oleanolic acid 1 exists widely in food,medicinal herbs and other plants and possesses many attractive biological activities. Recently,some oleanolic derivatives were reported to have interesting anti-tumor ***,using association principle of drug design,OA disaccharide 17 was designed and synthesized by coupling a-L-rhamnopyranosyl-（1→2）-a-L-arabinopyranosyl disaccharide moiety,which has proved to be a unique sugar sequence with strongly antitumor activity,and modified OA with a nitrile at C-17.

关键词： Oleanolic acid Rhamnopyranosyl Arabinopyranosyl Anti-tumor Association principle

Variation of lipids and fatty acids composition in the tissues of wild devil stinger(Inimicus japonicas)during sexual maturation

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Aquaculture and Fisheries 2018年第3期3卷 115-121页

作者： Songlin li wen wen Xu Gong Xuxiong Huang Naisong Chen National Demonstration Center on Experiment Teaching of Fisheries Science Shanghai Ocean UniversityShanghai 201306China Research Centre of the Agriculture Ministry on Environmental Ecology and Fish Nutrition Shanghai Ocean UniversityShanghai 20136China Shanghai Collaborative Innovation for Aquatic Animal Genetics and Breeding Shanghai Ocean UniversityShanghai 201306China

The present study was conducted to characterize the lipid and fatty acid profiles in different tissues(gonad,liver and muscle)of the wild-caught devil stinger during sexual ***-caught devil stinger were divided into six groups according to gonad development and *** lipid content was up to 40%dry weight in liver and was significantly higher than in other tissues(ovary,testis and muscle)in both male and female stinger during sexual *** maturation,total lipid content in the female stinger liver decreased,but in males significantly increased in all *** proportions of neutral lipids(NL)were observed in the stinger liver,while polar lipids(PL)were mainly quantified in the gonad and muscle of both male and female *** PL content of the ovary significantly decreased with sexual maturation,but NL were significantly *** fatty acids composition of the stinger broodstocks were tissue-and lipid *** the stinger gonad high-unsaturated fatty acids(HUFA),such as ARA,DHA and EPA,are selectively transferred and conserved,indicating the crucial role of these fatty acids during sexual maturation of this fish species.

关键词： lipids Fatty acids composition Gonad development Devil stinger

Improved Corrosion Resistance of Selective Laser Melted Ti–5Cu Alloy Using Atomized Ti–5Cu Powder

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Acta Metallurgica Sinica(English Letters) 2019年第8期32卷 1007-1014页

作者： Ying Han Hong-Rui Wang Yun-Dong Cao wen-Tao Hou Shu-Jun li School of Electrical Engineering Shenyang University of TechnologyShenyang 110870China Titanium Alloy Laboratory Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The different types of metal powder used for selective laser melting(SLM) process would cause distinct corrosion behavior due to the uniformity of the obtained *** SLM-produced Ti–5Cu alloy using atomized Ti–5Cu metal powder(SLMed Ti–5Cu) in this work reveals a relatively uniform microstructure with overwhelming acicular α/α′ phase and shows great advantages on corrosion resistance compared with the SLM-produced Ti–5Cu alloy using the mixture powder(SLMedM Ti–5Cu).The effect of the micro-galvanic cells decreases due to the undetectable Ti2Cu phase in the microstructure of the SLMed Ti–*** apparent passivation behavior was observed for SLMed Ti–5Cu instead of severe pitting phenomenon for the SLMed-M Ti–*** charge transfer resistance of SLMed Ti–5Cu in this work is 10.09 ± 2.63 MΩ cm2, which is significantly higher than that of SLMed-M Ti–5Cu(4.76 MΩ cm2).The above result indicates the atomized Ti–5Cu powder plays an important role in the formation of the uniform microstructure of SLMed product, thereby enhancing its corrosion resistance in Hank’s solution at 37 ℃.

关键词： Selective laser melting Corrosion behavior Uniform microstructure Ti-5Cu Passivation Polarization resistance

Ocular leech infestation initially misdiagnosed as conjunctival pigmented nevus

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International Journal of Ophthalmology(English edition) 2013年第4期6卷 557-558页

作者： wen-Wei li Ting Shen Jin Jiang Department of Ophthalmology Zhejiang Provincial People's Hospital School of Ophthalmology and Optometry Wenzhou Medical College

Dear sir,Iam ***-Wei li,from the Department of Ophthalmology,Zhejiang Provincial People’s Hospital,Hangzhou,China.I write to present a case of ocular leech infestation initially misdiagnosed as conjunctival pigmented... 详细信息

关键词： Ocular leech infestation initially misdiagnosed as conjunctival pigmented nevus body Figure

Acid leaching kinetics of zinc plant purification residue

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Transactions of Nonferrous Metals Society of China 2013年第9期23卷 2786-2791页

作者：李倩张宝闵小波申文前中南大学冶金与环境学院长沙410083 武警工程大学理学院西安710086

The leaching processes of zinc plant purification residue in sulfuric acid solution were investigated with respect to the effects of sulfuric acid concentration, reaction temperature, and particle size. A particle size of 75？80 μm was required to leach 99.8%cobalt and 91.97%zinc at 70 °C for 20 min when the sulfuric acid concentration was 100 g/L and the ratio of liquid to solid was 50？1 （mL/g）. The leaching kinetics of zinc plant purification residue in sulfuric acid solution system conformed well to the shrinking core model, and the dissolution rates of cobalt and zinc were found to be controlled by diffusion through a porous product layer. The apparent activation energy values of cobalt and zinc reaction were calculated to be 11.6931 kJ/mol and 6.6894 kJ/mol, respectively, according to the Arrhenius formula equation. The results show that diffusion through the inert particle pores is the leaching kinetics rate-controlling step.

关键词： cobalt zinc acid leaching leaching kinetics