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Impact of climatic factors on vegetation dynamics in the upper Yangtze River basin in China

Journal of Mountain Science 2020年第5期17卷 1235-1250页

作者： ZHANG Yu-xin wang Yu-kuan FU Bin DIXIT Amod Mani CHAUDHARY Suresh wang Shan Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China National Society for Earthquake Technology-Nepal Kathmandu LalitpurP.0.Box 13667Nepal Chengdu Land Planning and Cadastre Center Chengdu 610074China

It is necessary to understand vegetation dynamics and their climatic controls for sustainable ecosystem *** study examines the vegetation dynamics and the effect of climate change on vegetation growth in the pristine conditions of 58 woodland National Nature Reserves(NNRs)located in the upper Yangtze River basin(UYRB)in China which are little influenced by human *** in the normalized difference vegetation index(NDVI),precipitation,and temperature in the selected NNRs were observed and analyzed for the period between 1999 and *** relationship between time-lag effect of climate and changes in the NDVI were assessed using Pearson *** results showed three major trends.1)The NDVI increased during the study period;this indicates an increase in the amount of green vegetation,especially due to the warmer climate during the growing *** NDVIs in March and September were significantly affected by the temperature of the previous *** temperatures increased significantly(Pdelay between climatic factors and their effect on vegetation,which depended on the previous *** particular,the spring temperature had a delayed effect on the NDVI in summer.2)The way in which vegetation responds to climatic factors varied significantly across the *** had a greater effect on the NDVI in spring and summer and the effect was greater at higher altitudes.A similar trend was observed for precipitation,except for altitudes of 1000–2000 m.3)Temperature had a greater effect on the NDVI in spring and autumn at higher *** same trend was observed for precipitation in *** findings suggest that the vegetation found in NNRs in the upper reaches of the Yangtze River was in good condition between 1999 and 2015 and that the growth and development of vegetation in the region has not been adversely affected by climate *** demonstrates the effectiveness of nature reserves in protectin

关键词： National Nature Reserves Upper Yangtze River basin Normalized difference vegetation index Climate change Correlation analysis

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Cropland physical disturbance intensity： plot-scale measurement and its application for soil erosion reduction in mountainous areas

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Journal of Mountain Science 2018年第1期15卷 198-210页

作者： LI Ming wang Yu-kuan XU Pei FU Bin TIAN Cong-shan wang Shan Institute of Mountain Hazards and Environment The Chinese Academy of Sciences Chengdu 610041 China University of Chinese Academy of Sciences Beijing 100049 China Chengdu Land Planning and Cadastre Center Chengdu 610074 China

Various kinds of human disturbances on cropland are the main reasons for soil erosion and land *** practices in mountainous areas vary greatly among cropland plots because of the heterogeneity of biophysical conditions and differences in farmers'management *** main purpose of this paper is to develop a composite index of cropland physical disturbance intensity(CLDI)to reflect the plot-scale discrepancy of potential soil erosion in mountainous *** study was based on both plot survey and household interview data,collected from six typical catchments in mountainous areas of southwestern *** kinds of physical disturbance practices and two kinds of conservation practices during one crop rotation period were synthesized to develop the CLDI *** rough set theory was referenced to avoid subjectivity during weight *** results show that conventional tillage,deep fertilization,and manual weeding are the main causes of cropland soil erosion,whereas manure application in combination with seasonal fallow reduces soil *** crop types as well as cropland location factors determine the spatial pattern of *** rotation modes with major crops of tobacco and maize resulted in a maximal CLDI,and cropland plots with a distance radius of 150 meters away from households received the most intensive physical *** results are critical to help better protect rural environments in mountainous *** on the results,methods to reduce cropland soil erosion are suggested.

关键词： Cropland disturbance intensity Soil erosion Farming practices Farmers' behavior Rough set theory Index development

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A New Maleamide Bridged Carbazole Chromogenic-sensor Based on Proton Transfer Signaling Mode

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Chemical Research in Chinese Universities 2008年第3期24卷 263-265页

作者： wang Yue-hong LIN Hai SHAO Jie LIN Hua-kuan department of Chemistry for Absorption and Separation of Ministry of Education Nankai University Tianjin 300071 P R. China Key Laboratory of Functional Polymer Materials for Absorption and Separation of Ministry of Education Nankai University Tianjin 300071 P R. China

A Maleamide bridged carbazole receptor was designed and synthesized, the interactions between the receptor and anions, such as Ac-, H2PO4-, OH-, F-, Cl-, Br- and I- in DMSO were investigated by UV-Vis spectroscopy and 1H NMR titration. The results of UV-Vis spectral studies indicate that interactions existed between receptor and anions, which induced remarkable color changes. The 1H NMR titration indicated amide moiety of the receptor was deprontonated first when a small quantity of anions such as Ac-, H2PO4-, F- were added; however, the carbazole N―H was gradually deprontonated upon the addition of anions.

关键词： Anion receptor Colorimetric Supramolecular chemistry

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BCDC： A High-Performance, Server-Centric Data Center Network

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Journal of Computer Science & Technology 2018年第2期33卷 400-416页

作者： Xi wang Jian-Xi Fan Cheng-kuan Lin Jing-Ya Zhou Zhao Liu School of Computer Science and Technology Soochow University Suzhou 215006 China School of Software and Services Outsourcing Suzhou Institute of Industrial Technology Suzhou 215004 China

The capability of the data center network largely decides the performance of cloud computing. However, the number of servers in the data center network becomes increasingly huge, because of the continuous growth of the application requirements. The performance improvement of cloud computing faces great challenges of how to connect a large number of servers in building a data center network with promising performance. Traditional tree-based data center networks have issues of bandwidth bottleneck, failure of single switch, etc. Recently proposed data center networks such as DCell, FiConn, and BCube, have larger bandwidth and better fault-tolerance with respect to traditional tree-based data center networks. Nonetheless, for DCell and FiConn, the fault-tolerant length of path between servers increases in case of failure of switches; BCube requires higher performance in switches when its scale is enlarged. Based on the above considerations, we propose a new server-centric data center network, called BCDC, based on crossed cube with excellent performance. Then, we study the connectivity of BCDC networks. Furthermore, we propose communication algorithms and fault-tolerant routing algorithm of BCDC networks. Moreover, we analyze the performance and time complexities of the proposed algorithms in BCDC networks. Our research will provide the basis for design and implementation of a new family of data center networks.

关键词： data center network interconnection network crossed cube server-centric fault-tolerant

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Spoken dialog summarization system with HAPPINESS/SUFFERING factor recognition

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Frontiers of Computer Science 2017年第3期11卷 429-443页

作者： Yang-Yen OU Ta-Wen kuan Anand PAUL Jhing-Fa wang An-Chao TSAI department of Electronic Engineering Cheng Kung University Talnan 701 China department of Computer Science and Engineering Kyungpook National Univeristy Daegu 702-701 Korea department of Digital Multimedia design Tajen University Pingtung 741 China

This work presents a spoken dialog summariza- tion system with HAPPINESS/SUFFERING factor recognition. The semantic content is compressed and classified by factor categories from spoken dialog. The transcription of au- tomatic speech recognition is then processed through Chinese Knowledge and Information Processing segmentation system. The proposed system also adopts the part-of-speech tags to effectively select and rank the keywords. Finally, the HAPPINESS/SUFFERING factor recognition is done by the proposed point-wise mutual information. Compared with the original method, the performance is improved by applying the significant scores of keywords. The experimental results show that the average precision rate for factor recognition in outside test can reach 73.5% which demonstrates the possi- bility and potential of the proposed system.

关键词： spoken dialog summarization keyword extraction natural language processing (NLP) sentiment analysis

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Planning conservation corridors in mountain areas based on integrated conservation planning models: A case study for a giant panda in the Qionglai Mountains

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Journal of Mountain Science 2019年第11期16卷 2654-2662页

作者： LU Ya-feng Li Qin-wen wang Yu-kuan XU Pei Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China

With the accelerated urbanization,human activities pose serious threats to species because of *** conservation corridors between habitats could improve species mobility in order to address the human ***,there are a limited number of studies that focus on assessing the effect of human activities on species movement in mountain areas as well as how to integrate different conservation models relating to conservation corridors *** our study,we modified the resistance model and took land use data as input parameters to quantify the impacts of human activities in mountain ***,different conservation planning models,including Circuit model and Least Cost Path(LCP)algorithm,were ***,our approach was applied to identify giant panda corridors in Miarro nature reserve,Caopo nature reserve,and Wolong nature *** results suggested that the impacts of human activities were limited in valley regions due to topography by resistance ***,Circuit model demonstrated that the conservation corridors for giant panda could not be identified between the Miarro and the Caopo nature ***,more detailed corridors between habitats were planned by the LCP ***,we also identified bottlenecks for migration in each corridor,indicating that human activities’interference was the primary *** approach not only could connect habitats for conservation in mountain areas but also found out that the corridor could not be identified between habitats.

关键词： Corridors Human activities Mountain areas Giant panda

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deciphering the critical effect of cathode-electrolyte interphase by revealing its dynamic evolution

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Journal of Energy Chemistry 2023年第6期81卷 192-199,I0006页

作者： Zhengfeng Zhang Changdong Qin kuan wang Xiao Han Jinhui Li Manling Sui Pengfei Yan Beijing Key Laboratory of Microstructure and Property of Solids Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China

Cathode electrolyte interphase(CEI)layer plays a crucial role in determining the electrochemical performance of lithium-ion *** by the sensitive nature of CEI and the lack of characterization techniques,its dynamic evolution during cycling,its formation mechanism,and its specific impact on battery performance are not yet fully ***,we systematically investigate the dynamic evolution of CEI layer and its critical effect on the cycling performance of LiCoO_(2)cathode by diverse characterization *** find that cycling voltage plays a key role in affecting CEI formation and evolution,and a critical potential(4.05 V ***)is identified,which acts as the switching potential between CEI deposition and *** show that CEI starts deposition in the discharge process when the potential is below 4.05 V,and CEI decomposition occurs when the potential is higher than 4.05 *** the battery is cycled below such a critical potential,a stable CEI layer is developed,which leads to superior cycling *** the battery is cycled above such a critical potential,a CEI-free cathode interface is observed,which also demonstrates good cycle ***,when the critical potential falls in the cycling voltage range,CEI deposition and decomposition are repeatedly switched on during cycling,leading to the dynamically unstable CEI *** unstable CEI layer causes continuous interfacial reaction and degradation,resulting in battery performance *** work deepens the understanding of the CEI formation and evolution mechanisms,and clarifies the critical effect of CEI layer on cycling performance,which provides new insights into stabilizing the electrode-electrolyte interface for high-performance rechargeable batteries.

关键词： LiCoO_(2) CEI Lithium-ion battery Electron microscopy XPS

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Optimally Embedding 3-Ary n-Cubes into Grids

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Journal of Computer Science & Technology 2019年第2期34卷 372-387页

作者： Wei-Bei Fan Jian-Xi Fan Cheng-kuan Lin Yan wang Yue-Juan Han Ru-Chuan wang School of Computer Science and Technology Soochow University Suzhou 215006 China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing 210003 China College of Mathematics and Computer Science Fuzhou University Fuzhou 350108 China

The 3-ary n-cube,denoted as Qn3,is an important interconnection network topology proposed for parallel computers,owing to its many desirable properties such as regular and symmetrical structure,and strong scalability,among *** this paper,we first obtain an exact formula for the minimum wirelength to embed Qn3 into *** then propose a load balancing algorithm for embedding Qn3 into a square grid with minimum dilation and ***,we derive an O(N2)algorithm for embedding Qn3 into a gird with balanced communication,where N is the number of nodes in *** experiments are performed to verify the total wirelength and evaluate the network cost of our proposed embedding algorithm.

关键词： 3-ary n-cube embedding algorithm grid interconnection network

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Soluble Polyimide-reinforced TGDDM and DGEBA Epoxy Composites

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Chinese Journal of Polymer Science 2020年第8期38卷 867-876,I0007页

作者： Qi Chen Shun wang Feng Qin kuan Liu Qian Liu Qing Zhao Xing-Yi wang Yan-Hong Hu Research Institute of Industrial Catalysis School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China Key Laboratory for Specially Functional Polymers and Related Technology of Ministry of Education School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

Polyimide(PI)synthesized from aromatic diamine and dianhydrides via two-step poly-condensation method was highly soluble in TGDDM(MY-720)and DGEBA(E-51)at desirable ***-PI(M-PI)and DGEBA-PI(E-PI)composites within 0.5%-3%PI loading could be prepared without organic *** the cryogenically fractured surfaces of M-PI and E-PI composites,no obvious heterogeneous phase was observed by *** mechanical properties were promoted significantly by PI,especially for impact *** 2%PI-2W into MY-720 and E-51 composites,the impact strength increased to 21 and 51 kJ/m2,the tensile strength increased by 62%and 19%,and the flexural strength by 18%and 13%,respectively,with slight increases in tensile *** results were related to the promotion in plasticity of composites and changes in fragile→ductile fracture ***,Tg and thermal stability of M-PI and E-PI were increased effectively.

关键词： Polyimide TGDDM and DGEBA epoxy resin Impact strength Toughness

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Impacts of future climate change(2030-2059)on debris flow hazard:A case study in the Upper Minjiang River basin,China

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Journal of Mountain Science 2018年第8期15卷 1836-1850页

作者： LI Ming TIAN Cong-shan wang Yu-kuan LIU Qin LU Ya-feng wang Shan Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 510041China University of Chinese Academy of Sciences Beijing 100049China Chengdu University of Technology Chengdu 610059China Chengdu Land Planning and Cadastre Center Chengdu 610074China

An increase in extreme precipitation events due to future climate change will have a decisive influence on the formation of debris flows in earthquake-stricken areas. This paper aimed to describe the possible impacts of future climate change on debris flow hazards in the Upper Minjiang River basin in Northwest Sichuan of China, which was severely affected by the 2008 Wenchuan earthquake. The study area was divided into 1285 catchments, which were used as the basic assessment units for debris flow hazards. Based on the current understanding of the causes of debris flows, a binary logistic regression model was used to screen key factors based on local geologic, geomorphologic, soil,vegetation, and meteorological and climatic conditions. We used the weighted summation method to obtain a composite index for debris flow hazards, based on two weight allocation methods: Relative degree Analysis and rough set theory. Our results showed that the assessment model using the rough set theory resulted in better accuracy. According to the bias corrected and downscaled daily climate model data, future annual precipitation(2030-2059) in the study area are expected to decrease, with an increasing number of heavy rainfall events. Under future climate change, areas with a high-level of debris flow hazard will be even more dangerous, and 5.9% more of the study area was categorized as having a high-level hazard. Future climate change will cause an increase in debris flow hazard levels for 128 catchments, accounting for 10.5% of the total area. In the coming few decades, attention should be paid not only to traditional areas with high-level of debris flow hazards, but also to those areas with an increased hazard level to improve their resilience to debris flow disasters.

关键词： debris flow Hazard assessment Relative degree analysis Rough set theory Future climate change Minjiang River basin

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