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Change of surface cover greenness in China between 2000 and 2010

Chinese science Bulletin 2012年第22期57卷 2835-2845页

作者： LIU Shuang1,4. GONG Peng1,2,31state Key Laboratory of Remote Sensing science, Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of sciences,and Beijing Normal university, Beijing 100101, China 2Institute for Global Change Studies & Center for Earth System science, Tsinghua university, Beijing 100084. China 3department of Environmental science, Policy and Management, university of California, Berkeley, CA94.20, usa 4.raduate university of Chinese Academy of sciences, Beijing 10004., China state Key Laboratory of Remote Sensing science Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China Graduate university of Chinese Academy of sciences Beijing China Institute for Global Change Studies & Center for Earth System science Tsinghua University Beijing China department of Environmental science Policy and Management University of California Berkeley USA

Surface greenness reflects the situation of vegetation *** index calculated from the Red and Near Infrared bands of remote sensing images,whose values indicate the level of photosynthetic activity,is monotonically related to surface greenness when vegetation canopy does not fully cover the background *** for desert regions,vegetation index is positively correlated with vegetation ***,vegetation index can be used to study the change in greenness of desert *** study collected MODIS Normalized Difference Vegetation Index (NDVI) data from 2000 to 2010 and analyzed their change over China in this *** results showed that an increasing trend of NDVI occurred over 66.84. (OLS fitting) or 64.27% (LAD fitting) of China,indicating that China's greenness is increasing ***,desertification of China *** showing large increase in greenness are found in Shaanxi,Shanxi,Ningxia,Henan,Shandong,Qinghai,and Gansu while regions with large decrease in greenness are found in Northeast Inner Mongolia,South Tibet,Jiangsu,and *** of Qinghai,Gansu,Xinjiang and South Tibet could probably be driven by climate *** of greenness in Northeast Inner Mongolia was related to agricultural *** of greenness in Jiangsu and Shanghai was related to rapid *** factors did not exhibit obvious correspondence to the large increase in greenness in Shaanxi,Shanxi,Ningxia and Gansu,indicating that the changes might have been caused by human *** reduction of desert areas in China could probably have been caused by human management and protection at the national scale.

关键词：中国地表覆盖归一化植被指数植被覆盖度沙漠地区 NDVI 西藏南部气候因素

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s-ordering operator expansions of quantum-mechanical fundamental representations and their applications

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science China(Physics,Mechanics & Astronomy) 2011年第12期54卷 2150-2154页

作者： FAN HongYi 1,3 , XU YeJun 2 & YUAN HongChun 3,4.1 department of Materials science and Engineering, university of science and Technology of China, Hefei 230026, China 2 department of Physics Electronic and Engineering, Chizhou university, Chizhou 24.000, China 3 department of Physics, Shanghai Jiao Tong university, Shanghai 200030, China 4.College of Optoelectronic Engineering, Changzhou Institute of Technology, Changzhou 213002, China 1. department of Materials science and Engineering University of Science and Technology of China Hefei 230026 China3. Department of Physics Shanghai Jiao Tong University Shanghai 200030 China2. Department of Physics Electronic and Engineering Chizhou University Chizhou 247000 China4. College of Optoelectronic Engineering Changzhou Institute of Technology Changzhou 213002 China

We show that the quantum-mechanical fundamental representations, say, the coordinate representation, the coherent state representation, the Fan-Klauder entangled state representation can be recast into s-ordering operator expansion, which is elegant in form and has many applications in deriving new operator identities. This demonstrates that Dirac's symbolic method can be merged into Newton-Leibniz integration theory in a broad way.

关键词： s-ordering operator expansion operator identities quantum mechanical representation

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Simultaneous structure and geometry detail completion based on interactive user sketches

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science China(Information sciences) 2012年第5期55卷 1123-1137页

作者： YANG Shen 1,QI Yue 1 & QIN Hong 2 1 state Key Laboratory of Virtual Reality Technology and Systems,Beihang university,Beijing 100191,China 2 department of Computer science,state university of New York at Stony Brook,Stony Brook,New York 11794.4.00,usa 1. state Key Laboratory of Virtual Reality Technology and Systems Beihang University Beijing 100191 China2. Department of Computer Science State University of New York at Stony Brook Stony Brook New York 11794-4400 USA

We articulate a novel approach to geometric model completion via interactive sketches in this ***,the initial incomplete model (with holes) is decomposed into a base model and a high-frequency component,which represents global rough shape and geometric details,*** then repair the base model via smooth hole-filling,and compute the geometry detail image using high frequency *** novel element of our approach is that we allow users to interactively sketch a few structural curves that span across hole regions,with a goal to repair both local geometric details and global *** the help of local parameterization,we convert detailed geometry into gradient-domain images which can propagate along user-specified *** integrating recovered gradient-domain images and base shape,we can generate a complete model that faithfully recovers both global structure and local *** salient contribution of this paper is the unified approach for user interaction,global structure,and geometry details towards high-fidelity model *** demonstrate our new approach using a number of examples that exhibit salient global structure as well as local geometry details.

关键词： model repair geometric modeling interactive sketch 3D graphics

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VMckpt:lightweight and live virtual machine checkpointing

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science China(Information sciences) 2012年第12期55卷 2865-2880页

作者： LIU HaiKun 1,JIN Hai 1,LIAO XiaoFei 1,MA Bo 1 & XU ChengZhong 2 1 Services Computing Technology and System Lab,Cluster and Grid Computing Lab,School of Computer science and Technology,Huazhong university of science and Technology,Wuhan 4.0074.China 2 department of Electrical and Computer Engineering,Wayne {4. university,Detroit,MI 4.202,usa 1. Services Computing Technology and System Lab Cluster and Grid Computing Lab School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China2. Department of Electrical and Computer Engineering Wayne State University Detroit MI [48202 USA

Recent advance of virtualization technology provides a new approach to check-point/restart at the virtual machine(VM) *** contrast to traditional process-level checkpointing,checkpointing at the virtualization layer brings up several advantages,such as compatibility,transparence,flexibility and ***,because the virtualization layer has little semantic knowledge about the operation system and the applications running atop,VM-layer checkpointing requires saving the entire operating system state rather than a single *** overhead may render the approach *** reduce the size of VM checkpoint,in this paper we propose a page eviction scheme and an incremental checkpointing mechanism to avoid saving unnecessary VM pages in the *** keep the system online transparently,we propose a live checkpointing mechanism by saving the memory image in a copy-on-write(COW) *** implement the performance optimization mechanisms in a prototype system,called *** results with a group of representative applications show that our page eviction scheme and incremental checkpointing can significantly reduce the checkpoint file size by up to 87% and shorten the total checkpointing/restart time by a factor of up to 71%,in comparison with the Xens default checkpointing *** observed application downtimes due to checkpointing can be reduced to as small as 300 ms.

关键词： checkpoint/restart copy-on-write page eviction virtual machine

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AUTOMATED REASONING IN DIFFERENTIAL GEOMETRY AND MECHANICS USING THE CHARACTERISTIC METHOD Ⅳ. Bertrand Curves

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Systems science and Mathematical sciences 1993年第2期6卷 186-192页

作者： CHOU Shangching GAO Xiaoshan department of Computer science,the Wichita state university,Wichita,KS 67260,{4. Institute of Systems science, Academia Sinica, Beijing 100080, China The Wichita state university 美国中科院系统科学所北京

This paper reports the study of properties of the curve pairs of the Bertrandtypes using our automated reasoning program based on Wu’s method of mechanical the-orem proving for differential geometry. A complete list of results about Bertrand curvesin metric and affine spaces is derived mechanically. The list includes most of the knownresults of various Bertrand curves. We also derive some new results about Bertrand curves.

关键词： Mechanical theorem proving metric differential geometry affine differential geometry Bertrand curves

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Multistage evolution of continental collision orogen:A case study for western Dabie orogen

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Chinese science Bulletin 2009年第15期54卷 2568-2579页

作者： WU YuanBao state Key Laboratory of geological Processes and Mineral Resources, Faculty of Earth sciences, China university of Geosciences, Wuhan 4.0074. China state Key Laboratory of Continental Dynamics, department of Geology, Northwest university, Xi’an 710069, China state Key Laboratory of geological Processes and Mineral Resources Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China state Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an 710069 China

The foramtion and evolution of collisional orogen is a prominent feature along convergent plate margins, and is generally a complex process. This article presents an integrated study of zircon genesis, U-Pb age and Lu-Hf isotope composition as well as geological characteristics for the western Dabie orogen to constrain its multi-stage evolution history. The results suggest that the formation of oceanic crust in the Huwan area was constrained at ca. 4.0―4.0 Ma, which was slightly later than the collision of the northern Qinling with the North China Block. It formed in a marginal basin in the northern margin of the Yangtze Block. The peak metamorphism of eclogite in the Huwan area occurred at ca. 310 Ma, and the timing of the initial exhumation of oceanic eclogite was about 270 Ma. The high to ultrahigh pressure (HP-UHP) metamorphic rocks in the Xinxian and the Hong'an metamorphic zones have the same ages and natures as those of the HP-UHP metamorphic rocks in the other Dabie-Sulu terrains, and also have experienced multi-stage exhumation, and thus can be taken as a coherent part of the Dabie-Sulu orogen. Therefore, the Qinling-Dabie-Sulu orogen is a typical multi-stage continental collision orogen, with an amalgamation process extending more than 200 Ma.

关键词：大别造山带大陆碰撞西部演变超高压变质岩碰撞造山带苏鲁造山带变质岩区

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Soil Water Hysteresis at Low Potential

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Pedosphere 2007年第4期17卷 436-444页

作者： L.PRUNTY J.BELL department of Soil science North Dakota state university FargoND 58105 (USA)

Knowledge of the soil water characteristic curve is fundamental for understanding unsaturated *** objective of this work was to find scanning hysteresis loops of two fine textured soils at water potentials below wilting *** was done by equilibration over NaCl solutions with water potentials of-6.6 to-18.8 MPa at 25℃.When cycled repeatedly through a series of potentials in the range noted previously both soils exhibited a hysteresis *** experimental differences in water content between the drying and wetting soils at the same water potential were much too large to be accounted for by failure to allow sufficient time to attain equilibrium as predicted by the exponential decay *** wetting versus drying differences were relatively small,however,at only 4.mg g-1 or less in absolute terms and about 3% of the mean of wetting and drying,in relative *** should be a consideration when modeling biological and physical soil processes at water contents below the wilting point,where small differences in water content result in large potential energy changes.

关键词： adsorption dry soil equilibration matric potential soil water characteristic

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ON THE THEORY OF RESOLVENTS AND ITS APPLICATIONS

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Systems science and Mathematical sciences 1999年第S1期12卷 17-30页

作者： GAO Xiaoshan(Institute of Systems science, Academia Sinica,Beijing 100080, China)Shang-Ching Chou(department of Computer science, The Wichita state {4., Wichita,KS 67208, usa)

We extend the concept of the resolvent of a prime ideal to the concept of theresolvent of a general ideal with respect to a set of parameters and propose an algorithmto construct the generalized resolvents based on Wu-Rits’s zero decomposition *** generalized algorithm has the following applications. (1) For a reducible variety V,we can find a direction on which V is projected birationally to an irreducible hypersurface.(2) We give a new algorithm to find a primitive element for a finite algebraic extensionof a field of characteristic zero. (3) We present a complete method of finding parametricequations for algebraic curves. (4. We give a method of solving a system of polynomialequations to any given precision.

关键词： Resolvents parameterization of algebraic curves primitive elements polynomial equation solving Wu-Ritt’s decomposition algorithm.

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Transport network and flow mechanism of shallow ore-bearing magma in Tongling ore cluster area

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science China Earth sciences 2006年第4期49卷 397-407页

作者： DENG Jun1,2, WANG Qingfei1,2 , HUANG Dinghua3 , WAN Li4. YANG Liqiang1,2 & GAO Bangfei1,2 1. state Key Laboratory of geological Processes and Mineral Resources, China university of Geosciences, Beijing 100083, China 2. Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, China university of Geo- sciences, Beijing 100083, China 3. Faculty of Earth sciences, China university of Geosciences, Wuhan 4.0074. China 4. School of Mathematics and Information science, Guangzhou university, Guangzhou 5104.5, China 1. state Key Laboratory of geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing 100083 China 3. Faculty of Earth sciences China University of Geosciences Wuhan 430074 China 4. School of Mathematics and Information science Guangzhou University Guangzhou 510405 China

Abundant studies revealed that shallow intrusions of the Yanshanian epoch resulted in the mass mineralization of the Tongling region. Various evidences showed there existed a concealed magma chamber at ?10 km depth in the middle part of this region during Yanshanian epoch, from which the ore-forming magma was generated and then transported to the superficial layer. Yet the transport network and flow mechanism of the shallow ore-bearing magma, the key problem associ- ated with ore-forming process, was relatively little focused on. Integrate analysis of structural me- chanics, statistical fractal and geological facts suggested that NE trending high-angle fold-related thrust faults and the tessellated basement ones served as the main pathways for the shallow magma’s transporting, moreover, the saddle void spaces among adjacent strata in the folds upon this fault system provided the place for magma’s emplacement. So the folds in the upper part and faults in the lower part of the upper crust constituted the fluid’s transport and emplacement network. During the deformation of geologic body with multi-layer structure, the layers in the upper part tended to fold when received the jacking stress from the lower part, while the lower one inclined to fault undergoing loads of the upper part. And the producing probability of this structure assemblage was highly in- creased in the condition, such as in the Tongling area, that the mechanic rigidity of the lower layers was stronger than that of the upper ones. For the pre-existence of fluid-conducting network, the top magma with high volatile in the magma chamber transported rapidly to the superficial layer in dyking pattern, located in the void spaces of folds, filled and reconstructed them. The sudden drop of pres- sure caused the fluid unmixing from the magma and mass ore-forming elements concentration. Pulse activity of the dyking may be the principal reason why magmatic bodies in the Tongling area were spatially-temporally con

关键词： Tongling, structural network, magma intrusion, fractal, dyke.

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Fuzzy tolerance quotient spaces and fuzzy subsets

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science China(Information sciences) 2010年第4期53卷 704-714页

作者： ZHANG Ling1 & ZHANG Bo2,3,4. 1Computer science & Technology College, Anhui university, Anhui 230039, China 2state Key Laboratory of Intelligent Technology and Systems, Beijing 100084. China 3Tsinghua National Laboratory of Information science & Technology, Beijing 100084. China 4.nformation science & Technology College, Computer science & Technology department, Tsinghua university, Beijing 100084. China 1. Computer science & Technology College Anhui University Anhui 230039 China2. State Key Laboratory of Intelligent Technology and Systems Beijing 100084 China3. Tsinghua National Laboratory of Information Science & Technology Beijing 100084 China4. Information Science & Technology College Computer Science & Technology Department Tsinghua University Beijing 100084 China

The structure and characteristic of fuzzy subsets are discussed by using the concepts of granulation and hierarchy in quotient space theory. First, the equivalence relation based quotient space theory is extended to the fuzzy tolerance relation. Second, the isomorphism and its discriminant of fuzzy tolerance relations are discussed. Finally, by using the fuzzy tolerance relation to define the fuzzy subset, its properties are addressed. The main results are given below: (1) several equivalent statements of fuzzy tolerance relations; (2) the definition of isomorphism of fuzzy tolerance relations; (3) the isomorphic discriminant of fuzzy tolerance relations; (4. the definition and properties of fuzzy subsets based on the fuzzy tolerance relations; and (5) the necessary and sufficient condition of the isomorphism of fuzzy subsets. These results will help us further comprehend the concepts of fuzzy tolerance relations and fuzzy subsets.

关键词： Fuzzy tolerance relation quotient space isomorphism fuzzy subset

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