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    25 January 2015, Volume 2015 Issue 1 Previous Issue    Next Issue
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    Article
    Ext-transfer for modular Lie algebras
    LI Yi-Yang
    2015, 2015 (1):  1-5.  doi: 10.3969/j.issn.1000-5641.2015.01.001
    Abstract ( 1127 )   PDF (163KB) ( 1521 )   Save
    Let G be a connected reductive algebraic group over an algebraically closed field k of prime characteristic p and g = Lie(G). This paper studied the Ext-groups of g with a p-character  of standard Levi form. An Ext-transfer result from g-modules to the modules of its Levi subalgebras was obtained. 
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    Notes on Chen’s inequalities for submanifolds of real space forms with a semi-symmetric non-metric connection
    ZHANG Liang, ZHANG Pan
    2015, 2015 (1):  6-15.  doi: 10.3969/j.issn.1000-5641.2015.01.002
    Abstract ( 1069 )   PDF (216KB) ( 1915 )   Save
    By using algebraic techniques, we proved Chen’s general inequalities for submanifolds of real space forms with a semi-symmetric non-metric connection, which generalized a result of C. ¨Ozg¨ur and A. Mihai. Also, a mistake of their paper has been modified.
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    null
    JIA Yang-Jie
    2015, 2015 (1):  16-26.  doi: 10.3969/j.issn.1000-5641.2015.01.003
    Abstract ( 1087 )   PDF (282KB) ( 1323 )   Save
    null
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    Cells of the weighted Coxeter group (B3, ?)
    MI Qian-Qian, SHI Jian-Yi
    2015, 2015 (1):  27-41.  doi: 10.3969/j.issn.1000-5641.2015.01.004
    Abstract ( 1027 )   PDF (319KB) ( 1310 )   Save
    The affine Coxeter group ( e B3, S) can be realized as the fixed point set of the
    affine Coxeter group ( e D4, eS) under a certain group automorphism α with α( eS) = eS. Let
    e? be the length function of e D4. We gave an explicit description for all the left cells of the
    weighted Coxeter group ( e B3, e?). Also§we showed that in the the weighted Coxeter groups
    ( e D4, e?) and ( e B3, e?), each left (respectively, two-sided) cell was left-connected (respectively,
    two-sided-connected).
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    Efficient characterization for I{2} and M{2}
    ZHENG Dao-Sheng
    2015, 2015 (1):  42-50.  doi: 10.3969/j.issn.1000-5641.2015.01.005
    Abstract ( 953 )   PDF (214KB) ( 1233 )   Save
    An important characterization formula for M{2} was given by Stewart where M 2 Cm×n. But this formula contains redundant arbitrary parameters, and therefore is nonefficient. This paper, by using the matrix full rank decomposition, showed that for a proper subset of I{2}s, which is denoted as B1, the redundant arbitrary parameters in Stewart’s formula can be eliminated, and I{2}s is a union set of its certain subsets, and each of the subsets is 2-norm isometry with B1. Finally, the efficient characterization fonmulas for I{2}s, I{2} and M{2} are obtained respectively. An algorithm was provided that can be used to compute any element of I{2}s, and avoid the repeat computation work for each
    element of I{2}s.
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    A general existence and uniqueness result on multidimensional BSDEs
    XU Shao-Ya, FAN Sheng-Jun
    2015, 2015 (1):  51-60.  doi: 10.3969/j.issn.1000-5641.2015.01.006
    Abstract ( 1172 )   PDF (215KB) ( 1653 )   Save
    This paper established a general existence and uniqueness result of solutions for multidimensional backward stochastic differential equations (BSDEs) whose generators satisfy the weakly monotonic condition in y, which generalizes some existing results.
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    Error bounds of regularized gap functions for smooth and nonmonotone variational inequality problems
    WANG Li-Na, LI Ming-Hua
    2015, 2015 (1):  61-67.  doi: 10.3969/j.issn.1000-5641.2015.01.007
    Abstract ( 986 )   PDF (189KB) ( 1245 )   Save
    By using a class of regularized gap functions for a variational inequality problem, two kinds of global error bounds of the nonmonotone variational inequality problem under some different conditions was established.
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    Lipschitz equivalence of dust-like Lalley self-affine sets
    LI Wen-Wen, MA Yu-Tian
    2015, 2015 (1):  68-74.  doi: 10.3969/j.issn.1000-5641.2015.01.008
    Abstract ( 1070 )   PDF (175KB) ( 1166 )   Save
    We consider a class of Lalley self-affine sets and show that two sets E and F from this class are Lipschitz equivalent if they are dust-like.
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    An oscillation result for some higher order linear differential equations
    HU Meng-Wei, HUANG Zhi-Gang, SUN Gui-Rong
    2015, 2015 (1):  75-83.  doi: 10.3969/j.issn.1000-5641.2015.01.009
    Abstract ( 1091 )   PDF (295KB) ( 1300 )   Save
    The distribution of zeros of solutions of higher order linear differential equations with entire coefficients was investigated by using complex oscillation theory of linear differential equations. It was proved that the exponent of convergence of zeros of every transcendental solution of the equations is infinite if given a small perturbation to one of the coefficients.
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    An analytic proof for the formula of the first order obstruction making the dimensions of Bott-Chern cohomology groups and Aeppli cohomology groups jumping
    LIN Jie-Zhu, YE Xuan-Ming
    2015, 2015 (1):  84-94.  doi: 10.3969/j.issn.1000-5641.2015.01.010
    Abstract ( 1407 )   PDF (332KB) ( 1421 )   Save
    Let X be a compact complex manifold, and let  : X ! B be a small deformation of X, the dimensions of the Bott-Chern cohomology groups or Aeppli
    cohomology groups may vary under this deformation. In [1], M. Schweitzer constructed a complex of sheaves L•p,q, and represented Bott-Chern cohomology groups or Aeppli cohomology groups as the cohomology groups of L•p,q. In [2], the author have studied this jumping phenomenon by studying the deformation obstructions of a hypercohomology class of a complex of sheaves B• p,q which is quasi-isomorphic to L• p,q[1]. In particular, they obtain an explicit formula for the obstructions. In this paper, the formula of the first order obstruction is proved in another way by using cohomology of L• p,q.
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    Single-value extension property for anti-diagonal operator matrices and their square
    CUI Miao-Miao, CAO Xiao-Hong
    2015, 2015 (1):  95-102.  doi: 10.3969/j.issn.1000-5641.2015.01.011
    Abstract ( 1102 )   PDF (269KB) ( 1559 )   Save
    In this paper, we mainly proved the equivalence of the perturbation of single-value extension property for anti-diagonal operator matrices and their square on an infinite dimensional separable Hilbert space.
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    Series expansions for three familiar irrational numbers with free parameters
    WEI Chuan-An, GONG Dian-Xuan, WANG Qin
    2015, 2015 (1):  103-113.  doi: 10.3969/j.issn.1000-5641.2015.01.012
    Abstract ( 1175 )   PDF (204KB) ( 1363 )   Save
    √2, √3and √5are important irrational numbers, but the series expansions for them are rare in the literature. In order to fill the gap, we established numerous series expansions for these numbers with free parameters in terms of the hypergeometric method.
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    On the independence number of edge chromatic critical graphs
    QI Lin-Ming, MIAO Lian-Ying, LI Wei-Qi
    2015, 2015 (1):  114-119.  doi: 10.3969/j.issn.1000-5641.2015.01.013
    Abstract ( 1082 )   PDF (235KB) ( 1535 )   Save
    In 1968, Vizing conjectured for any edge chromatic critical graph G = (V,E) with maximum degree Δ and independence number α(G), α(G)≤|V|/2. In this paper, we proved that α(G) ≤(3Δ-3)/(5Δ-3)|V| for Δ∈{9,10} and α(G) ≤(15Δ-42)/(23Δ-42)|V| for Δ∈{11, · · · , 46}
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    Harary index of unicyclic graphs with n vertices and k pendent vertices
    CAI Gai-Xiang, YU Gui-Dong, XING Bao-Hua
    2015, 2015 (1):  120-125.  doi: 10.3969/j.issn.1000-5641.2015.01.014
    Abstract ( 1172 )   PDF (184KB) ( 1693 )   Save
    The Harary index is defined as the sum of reciprocals of distances between all pairs of vertices of a connected graph. In this paper, the graph with the largest Harary index among all the unicyclic graphs with n vertices and k pendent vertices were investigated.
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    On limit points of the third largest Laplacian eigenvalues of graphs
    WU Ya-Rong
    2015, 2015 (1):  126-130.  doi: 10.3969/j.issn.1000-5641.2015.01.015
    Abstract ( 998 )   PDF (193KB) ( 1360 )   Save
    For a different parameter $b$, let $l_G(b)$ denote the second largest root of $b\mu(\mu-2)\!-\!(\mu-1)^2(\mu-3)\!=\!0$ $(b\!=\!0,1,\cdots)$ and $l_T(b)$ denote the second largest root of $b\mu(\mu-2)\!-\!(\mu-1)^2(\mu-3)\!-\!(\mu-1)(\mu-2)\!=\!0$$(b\!=\!0,1,\cdots)$. Firstly, we will prove that there exist sequences of graphs  $\{G_{n,b}\}(b\!=\!0,1,\cdots)$ and $\{T_{n,b}\}(b\!=\!0,1,\cdots)$ such that their limit points of the third largest Laplacian eigenvalues are $l_G(b)$ and $l_T(b)$, respectively. Secondly, we will prove that $l_G(b)$, $l_T(b)$ and $2$ are all of the limit points of the third largest Laplacian eigenvalues which are no more than 2
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    The linear arboricity of upper-embedded graph and secondary upper-embedded graph
    LYU Chang-Qing
    2015, 2015 (1):  131-135.  doi: 10.3969/j.issn.1000-5641.2015.01.016
    Abstract ( 1006 )   PDF (255KB) ( 1260 )   Save
    The linear arboricity of a graph $G$ is the minimum number of linear forests which partition the edges of $G$. In the present, it is proved that if a upper-embedded graph $G$ has $\Delta\geqslant 3\sqrt{4-3\varepsilon}$  then its linear arboricity is $\lceil\frac{\Delta}{2}\rceil$\,and if a secondary upper-embedded graph $G$ has $\Delta\geqslant 6\sqrt{1-\varepsilon}$ then its linear arboricity is $\lceil \frac{\Delta}{2}\rceil$, where $\varepsilon\leqslant0$. It improves the bound of the conclusion in [1]. As its application, the linear arboricity of a  triangulation graph on double torus is concluded
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    On the maximal matching energy of graphs
    WU Ting-Zeng
    2015, 2015 (1):  136-141.  doi: 10.3969/j.issn.1000-5641.2015.01.017
    Abstract ( 1086 )   PDF (251KB) ( 1450 )   Save
    The matching energy is defined as the sum of the absolute values of the zeros
    of the matching polynomial of a graph, which was firstly proposed by Gutman and Wagner
    (The matching energy of a graph, Discrete Appl. Math. 2012 (160): 2177õ2187). And
    they showed that the complete graph Kn had maximum matching energy in all graphs on
    n vertices. In this paper, among all graphs on n vertices, the graphs with i-th maximal
    matching energy are completely characterized, where i = 2, 3, . . . , 16.
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    The multi-object optimization of a spatial cable-driven parallel manipulator
    CHEN Jie, SUN Xiao-Long, MO Wei
    2015, 2015 (1):  142-150.  doi: 10.3969/j.issn.1000-5641.2015.01.018
    Abstract ( 1328 )   PDF (756KB) ( 1595 )   Save
    This paper investigates the multi-object optimization for a spatial 6-DOF (degree-of-freedom) cable-driven parallel manipulator. The optimization based on an NN (neural network)-genetic algorithm was carried out respectively with regarded to workspace volume, the minimum tension and global dexterity index, then three groups of satisfactory solutions were obtained. Furthermore, the weight coefficients for the multi-object optimization model were gained through the grey clustering method. The results show that the NN-genetic algorithm is effective for the structural optimization and can provide a useful reference for the optimal design of similar manipulators
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    K coverage of WiFi signal node deployment based on AFSA
    LI Zhong-Xiang, CHEN Lei
    2015, 2015 (1):  151-160.  doi: 10.3969/j.issn.10005641.2015.01.019
    Abstract ( 1042 )   PDF (4146KB) ( 1168 )   Save
    On the requirement of multiple wireless coverage in some hot applications like indoor positioning and navigation, multipath routing etc., this paper presented a K coverage placement scheme based on an improved Artificial FishSwarm Algorithm (AFSA). A simple obstacle interference describing model was also designed to make our simulation scenario closer to a real one. The simulative results showed that our method could obviously reduce the number of signal nodes and their aggregation on the premise of coverage.
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    An improved active contour model based on level set method
    WU Zhang, ZHU Min
    2015, 2015 (1):  161-171.  doi: 10.3969/j.issn.1000-5641.2015.01.020
    Abstract ( 1055 )   PDF (1226KB) ( 1550 )   Save
    By using the local regional information which has the ability to enhance the image, an improved active contour model based on level set method is proposed. Defining a novel SPF function with a nonnegative kernel function and local intensity clustering property, the novel model could draw upon intensity information in local regions at a controllable scale. In addition, the penalizing term which can be called distance regularization term drives the motion of the zero level set toward desired locations. Experimental results for real and synthetic images show the desirable proposed method performances and the model efficiency on intensity inhomogeneities and weak boundaries
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    A quantitative analysis technique for multi-classes access control model based on security entropy
    CHE Tian-Wei, MA Jian-Feng, WANG Chao, LI Na
    2015, 2015 (1):  172-177.  doi: 10.3969/j.issn.1000-5641.2015.01.021
    Abstract ( 979 )   PDF (297KB) ( 1284 )   Save
    To resolve the problem of quantitative analysis on classificatory information systems, a quantitative analysis technique is proposed based on security entropy. Firstly, the security entropy is put forward according to the information theory, to calculate the uncertainty of the system's determinations on the
    irregular access behaviors. Then the security theorems of classificatory information systems are defined based on security entropy. Finally, the typical access control models are analyzed by the technique, the technique's practicability is validated, and security and applicability of these models are compared. The result proves that the technique is suit for security quantitative analysis on access control model and evaluation to access control capability in information system
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    Angular distributions of photo-fragment ions of CH3OH molecules in the femtosecond laser fields
    FAN Qing-Fei, YANG Yan, WU Hua, ZHOU Bin, WANG Xiao, TENG Chong, SUN Zhen-Rong, WU Liang-Ping
    2015, 2015 (1):  178-185.  doi: 10.3969/j.issn.1000-5641.2015.01.022
    Abstract ( 1168 )   PDF (785KB) ( 1079 )   Save
    The multi-photon dissociation and coulomb explosion of methanol in the femtosecond laser field have been investigated by dc-slice imaging technique combined with time of flight mass spectroscopy. Time of flight mass spectroscopy and sliced images of fragment ions were obtained, and the kinetic energy release and angular distributions of photo-fragment ions were also measured. The kinetic energy release of CH2+,H2O+ and CH3+,OH+ meet the conservation of momentum, it is proved that they come from process of Coulomb explosion. Based on the comparison of the migration pathway and non-migration pathway from the C-O bond cleavage, the intensity dependence of the anisotropy parameter a2 and cos2θ values for each channel were calculated, which indicated the dynamic molecular alignments of methanol in the femtosecond laser fields dominates.
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    Ionization characteristics of the hydrogen ground state in an intense high-frequency laser field
    GAO Wan-Qin, WANG Jia-Xiang, ZHANG Ya-Yun
    2015, 2015 (1):  186-194.  doi: 10.3969/j.issn.1000-5641.2015.01.023
    Abstract ( 1102 )   PDF (1736KB) ( 1355 )   Save
    By using phase average method, the ionization dynamics of the hydrogen ground state (1s) under an intense high-frequency laser pulse has been studied in details. The influence of the laser frequency, polarization, pulse length and phase upon the ionization rate are explored. It is found that the ionization is very sensitive to the pulse phase. According to the steepness of the pulse rising and falling time, we found a “mixed regime” in the pulse phase, which can be used to explain the different dynamics of the ionization.
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    Research on parton distributions in nucleon
    XU Shi-Lei, RUAN Jian-Hong
    2015, 2015 (1):  195-202.  doi: 10.3969/j.issn.1000-5641.2015.01.024
    Abstract ( 1109 )   PDF (851KB) ( 1289 )   Save
    We present the parton distributions at leading order (LO) coming from GJR, MSTW and CTEQ parton sets and compare them at different momentum scales. Obvious differences exist in their gluon and sea quark distributions at small x region. Itindicates that people have not known the nucleon parton distributions very well. We analysze the influence of higher twist effects, i.e., the shadowing effects and anti-shadowing effects, on parton distributions. Because of the shadowing effects, the twist-4 gluon and sea quark distributions are smaller than the twist-2 distributions at small and middle x region, while, the anti-shadowing effects make the twist-4 gluon and sea quark distributions larger than the twist-2 distributions at x & 2 region. Finally, we present a detailed analysis of how the proton’s momentum is shared among various parton flavors at different Q2 for different parton sets. With the numerical calculation, we show that the MD-DGLAP equations are momentum conservation.
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    Resonant modes and peak gain analysis of LLC resonant converter
    ZHANG Li-Sheng
    2015, 2015 (1):  203-211.  doi: 10.3969/j.issn.1000-5641.2015.01.025
    Abstract ( 1911 )   PDF (944KB) ( 2023 )   Save
    LLC resonant converter has outstanding advantages in high power conversion efficiency and wide range adaptability of input voltage, but research on the peak gain is clearly insufficient. Therefore, the peak gain of LLC resonant converter is studied. According to the operation process of the series-parallel resonance, the converter can be divided into three resonant modes: inadequate resonant mode, complete resonant mode and over resonant mode. When the converter operates in complete resonant mode, it reaches its maximum value, and the corresponding switching frequency is named critical frequency. Finally, derivation of time-domain expression of the peak gain and the critical frequency is completed through the establishment of the converter state equations, and the accuracy of theoretical analysis is verified through simulation and experiment.
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    Investigation, oleaginousness of the major nonfood biodiesel plant resources in Shanghai, Jiangsu and Anhui provinces
    LI Xing-Lin, LIU Qiao-Xia, CHENG Zhi-Quan, HU Chao, GE Bin-Jie, LI Hong-Qing, TIAN Huai-Zhen
    2015, 2015 (1):  212-223.  doi: 10.3969/j.issn.10005641.2015.01.026
    Abstract ( 1358 )   PDF (606KB) ( 1381 )   Save
    The characteristics and distribution of the current Nonfood Biodiesel Plant (NFBP) resources in Shanghai, Jiangsu and Anhui provinces were investigated and the oil content of these plants were detected. The results showed that 151 species of energy plants in 59 families and 123 genera were of higher than 10% oil content. The oil content of some species such as Lindera chienii, L. angustifolia and L. rubronervia in Lauraceae, Euonymus maackii in Celastraceae, Vernicia fordii and Ricinus communis in Euphorbiaceae, Camellia sinensis in Theaceae were higher than 50%. Only Triadica sebifera were widely cultivated and utilized, Camellia oleifera and Vernicia fordi were less utilized, C. sinensis had not been utilized. Finally, some suggestions on the potential development were given according to the actual situation of NFBP resources in Shanghai, Jiangsu and Anhui provinces.
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    Analysis on regional industries based on input output table and SNA: A case of seven provinces in Eastern China
    SUN Lu, XUE Bing, GENG Yong, ZHANG Li-Ming
    2015, 2015 (1):  224-233.  doi: 10.3969/j.issn.10005641.2015.01.027
    Abstract ( 1621 )   PDF (947KB) ( 1844 )   Save
    Industrial relationship is the basis of investigating the industrial agglomeration, understanding the industrial structure and clarifying the industrial associations. By employing the methodology of Social Networking Analysis (SNA) based on the 2002 and 2007 InputOutput Table, this paper aims to carry out the quantitative study on the industrial relationship, measure the economic ties degree and identify the various functions of different industries. By taking the seven provincial regions located in Eastern China as cases, 42 industrial sectors are studied by calculating the cluster degree, nodes centrality, nodes intermediary, and closedegree to the center. The results show that, Shanghai has the highest industrial coupling degree while Anhui province is the lowest; the industries have different levels, and about 8 clusters have been formed, such a close industrial economic relationship means that the tendency of economic integration. The results of this study could provide quantitative analysis of industrial relationship and restructuring the industries.
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    Forecasting of Shanghai Port container throughput  under seasonal variation influence
    DU Gang, LIU Ya-Nan
    2015, 2015 (1):  234-239.  doi: 10.3969/j.issn.10005641.2015.01.028
    Abstract ( 1208 )   PDF (1401KB) ( 1780 )   Save
    It is very important for successful port operation and effective decisionmakingby forecasting container throughput accurately. The Autoregressive Integrated Moving Average model (ARIMA) and the Seasonal Autoregressive Integrated Moving Average model(SARIMA) are applied to the monthly data from 2007 to 2012 of Shanghai Port container throughput to forecast the container throughput of Shanghai Port. The seasonal variation of monthly port container throughputdata can be handled by SARIMA. Compared with ARIMA, SARIMA performed better and improved the Port container throughputprediction accuracy because of removing the seasonal variation.
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    Remote sensing and GIS based analysis of urban ecological  network in Pudong New Area, Shanghai
    ZHANG Lin, TIAN Bo, ZHOU Yun-Xuan, ZHU Chun-Jiao
    2015, 2015 (1):  240-251.  doi: 10.3969/j.issn.10005641.2015.01.000
    Abstract ( 1359 )   PDF (3405KB) ( 1900 )   Save
    Grassland, forest land and wetland are ecological habitats and elements of the basic urban ecological network of Pudong New Area in Shanghai. Due to the rapid growth in population and economy, the builtup area of Pudong New Area expands quickly, which result in the ecological habitats area decrease and fragmentation. The immediate consequences are the lowering of its ecological function and connectivity of the ecological networks. Using high resolution images from satellite FW2 acquired in 2011 and in combination with the ground investigations, we obtain the land use and land cover data of grass lands, forests land and wetlands by applying objectoriented remote sensing classification method and visualpostprocessing method. Supported by GIS techniques, we useseveral quantitative analysis algorithms, including Multilevel Weights, LeastCost Path and Gravity Model, to quantify the structure ofthe ecological network. The results show that: (1) the total area of grass lands, forest landsand wetlands in Pudong New Area is 179.9×103 hm2 , which is 65.41% of the total area; (2) there are few large patches with strong ecological suitability, and imbalanced along north-south direction; (3)the forest landsare the superior landscape type in the ecological network of the study area and make up 51.39% in the 10meterwidth ecological buffer zone; (4)Jiuduansha Wetland and Nanhui Dongtan Wildlife Sanctuary play important roles in ecological niche; and (5)land use structure changes rabidly with the increase of buffer distance, that is the ecological habitats reduce while building area increases.
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