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    25 May 2010, Volume 2010 Issue 3 Previous Issue    Next Issue
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    Article
    Experimental ecology research on destroyed evergreen broad leaved forests in TNFP, Zhejiang (Ⅳ): Contribution of seed bank to early restoration of destroyed evergreen broad leaved forests
    SONG Yaobin;ZHANG Qiping;DA Liangjun;
    2010, 2010 (3):  1-9. 
    Abstract ( 2529 )   PDF (1135KB) ( 2325 )   Save
    Four destroyed evergreen broadleaved forest plots were established by simulating the common disturbance types (removing trees, H>8 m; removing trees, H<8 m; removing all above ground plant; removing all aboveground plant and 010 cm depth surface soil) in Tiantong National Forest Park, in October, 2003. For understanding the contribution of seed bank to the restoration of destroyed evergreen broad leaved forests, the seed germination pattern, species composition, and the similarity between seed bank and the seedlings composition of first year restoration have been studied in this paper. The results showed that there were 995 seeds in seed bank and the seed abundance was 248.75 m-2, which belonged to 28 species, 27 genera and 21 families. The role of seed bank to 4 plots were Ⅰ (0.467) >Ⅳ (0.389) >Ⅱ (0.368) >Ⅲ (0). The pioneer species Sassafras tzumu , Alniphyllum fortunei , Clerodendrum cyrtophyllum , Litsea cubeba germinated and recruited abundantly from seed bank while the climax species Castanopsis carlesii and Lithocarpus glaber had little role to vegetation restoration. The species Choerospondias axillaries and Cinnamomum camphora mainly regenerated from exotic seed source. Conclusively, the soil seed bank exerted little role to the restoration of the evergreen broadleaved forests in this area.
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    Experimental ecology research on destroyed evergreen broad leaved forests in TNFP, Zhejiang (V): Five year recovery and regeneration of main trees after different disturbances
    QI Yu-feng;YANG Xu-feng;ZHANG Qi-ping;SONG Kun;KANG Min-ming;DA Liang-jun;
    2010, 2010 (3):  10-25. 
    Abstract ( 3363 )   PDF (1595KB) ( 1659 )   Save
    Investigations were carried out for 5 years from October, 2003 to October, 2008 in a logged evergreen broad leaved forest at Tiantong, Zhejiang province. Five following treatments were used in five sites: (Ⅰ) Big trees with height>8 m and DBH>5 cm were removed but sprouts retained; (Ⅱ) ground surface vegetation was removed but litter retained; (Ⅲ) all vegetation and 0 10 cm topsoil were removed. (Ⅳ) undergrowth was removed but big trees retained; and (Ⅴ) a control plot without any disturbance. Our results showed that: (1) The highest BAs (basal area value) were found in plot Ⅰ and plot Ⅱ, with a value of 1 631.8 cm2 and 1 619.4 cm2 respectively, and the lowest in plot Ⅳ with a value of 43.4 cm2. (2) The increase of BA in plot Ⅰ was mainly from the growth of retained evergreen broad leaved trees; plot Ⅱ had the highest BA increase which was mainly from deciduous broad leaved shrubs or small trees and deciduous broad leaved trees, and plot Ⅲ mainly from deciduous broad leaved shrubs or small trees and evergreen broad leaved trees; plot Ⅳ had few trees with low BAs. (3) Seedling and sapling recruitment fluctuated in all plots in 5 years. In plot Ⅰ and plot Ⅱ, seedlings and saplings were mainly evergreen broad leaved trees, but plot Ⅱ had more deciduous trees; seedlings and saplings in plot Ⅲ were mainly deciduous trees while in plot Ⅳ mainly evergreen broad leaved trees. Our results indicate that logging impact the recovery and regeneration of the evergreen broad leaved forest trees. Under logging big trees, evergreen broad leaved trees recover quickly; under clearing undergrowth, main trees recover slowly; under two kinds of clear cuttings, deciduous trees invade and dominate the plots or are mixed with evergreen broad leaved trees.
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    Experimental ecology research on destroyed evergreen broad leaved forests in TNFP, Zhejiang (Ⅵ): Leaf traits and ecological adaptation of five main dominant species during the early stage of restoration after different disturbances
    KANG Min-ming;ZHANG Qi-ping;DU Jing;SHEN Chen-chen;DA Liang-jun;
    2010, 2010 (3):  26-38. 
    Abstract ( 3391 )   PDF (1932KB) ( 2175 )   Save
    The maximum of net photosynthesis based on area (Amax), specific leaf area (SLA), and leaf nitrogen and phosphor concentration (N, P) of 5 main dominant species under 4 different degradation plots (removing trees, H>8 m; removing trees, H<8 m; removing all aboveground plant; removing all aboveground plant and 010 cm depth surface soil) were studied in Tiantong National Forest Park, Zhejiang province, China. The main results as follows. (1) Amax increased and SLA decreased along disturbance levels. (2) The low content of soil available P in plot Ⅲ (removing all aboveground plant and 010 cm depth surface soil) caused the significant declining of leaf P concentration. (3) Different main woody species owned different ecological adaptation to disturbance. Deciduous Litsea cubeba grew fast and dominated at the early stage of restoration with higher Amax, SLA, leaf N and P concentration. Schima superba had low leaf N and P concentration, while its Amax was high and had significant positive relationship with Amax.. Lithocarpus glaber had high leaf N concentration in degradation plots, which maintained at higher degree and was related positive with Amax significantly, and had high ability of defending leaf against high light. Castanopsis carlesii had medium Amax, SLA, leaf N and P concentration; its Amax and SLA had high plasticity, while leaf N concentration was steady. Castanopsis fargesii had low Amax and ability of the utilization of high light.
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    Real time near infrared light face detection based on morphology
    华东师范大学 计算机科学与技术系;上海 00
    2010, 2010 (3):  39-47. 
    Abstract ( 3144 )   PDF (1465KB) ( 1694 )   Save
    This new face detection algorithm first used Harr feature and Adaboost algorithm for locating the face area, and then normalized the area into specified size. Utilizing the property of high reflection rate under near infrared light on pupil, Quoit filter based on morphology was used for eye detection. In order to deal with difference sizes of pupil, a multi scale filter was proposed for reducing both of false positive rate and false negative rate. The experience showed that this method is accuracy and fast. And it fits the requirement of real time face detection
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    UML based design information extraction and its application in software refactoring
    LIU Chuan-bo;YANG Zong-yuan;XIE Jin-kui
    2010, 2010 (3):  48-57. 
    Abstract ( 2576 )   PDF (1362KB) ( 1415 )   Save
    By using UML(Unified Modeling Language) , this parer proposed a relationshipbased modeling method to support modeling and extraction the information contained in the design stage of software development. A prototype system was implemented. The extracted design information can be used in software refactoring, testing, as well as in aspectoriented programming. This approach is able to exploit the design phase semantic information and assist in software refactoring.
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    Enhanced low field magnetoresistance in nanostructured Sr2FeMoO6/CeO2 composites
    LI Xiang-Hu;LI Dan
    2010, 2010 (3):  57-62. 
    Abstract ( 2502 )   PDF (1540KB) ( 1386 )   Save
    The electric transport properties of the nanostructrued (Sr2FeMoO6)1- x/(CeO2) xcomposition were investigated. It was found that the lowfield magnetoresistance of the composition is higher than that of the pure Sr2FeMoO6/CeO2 material in the whole region of temperature. The magnetoresistance ratios at 10 K and 300 K with H=2 kOe for the x =0.3 sample are 1.7 times and 1.3 times as large as that for the pureSr2FeMoO6, respectively. This means that the spin dependent tunneling at the interfaces of grain boundaries is responsible for the enhanced MR.
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    Optimization of soft magnetic property for Co-based glass covered microwires
    YANG Qi-yan;ZHANG Qing;CHEN De-lu;ZHAO Zhen-jie
    2010, 2010 (3):  63-67. 
    Abstract ( 2430 )   PDF (1047KB) ( 1598 )   Save
    This paper studied the Giant Magnetoimpedance (GMI) and field sensitivity (ζ) of Cobased microwires with different diameters and under different annealing current densities, which was prepared by the TaylorUlitovsky method. The results showed that with the increase of diameters of the microwires the GMI and ζ both increase first and then decrease. The best soft magnetic property is obtained for the microwires with 29 μm in diameter. The highest field sensitivity (602 %/Oe ) is found under 120 A/mm2 current annealing.
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    Survey of the crossing number of graphs
    HUANG Yuan-qiu;WANG Jing
    2010, 2010 (3):  68-80. 
    Abstract ( 2732 )   PDF (362KB) ( 1556 )   Save
    This paper gave a comprehensive review of the studies of the crossing number in China and in the world during the last 60 years, from the following 4 aspects: The crossing number of some particular graphs, the lower bound of crossing numbers, parameters related to crossing numbers, and crossing numbers of other types.
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    Decycling squares of trees
    BAU Sheng;HOU Jian-ping
    2010, 2010 (3):  81-84. 
    Abstract ( 2681 )   PDF (278KB) ( 1410 )   Save
    A recursive relation for the decycling numbers of the squares of trees was established, together with an interpolation result on the decycling numbers of the squares of trees of order n. The results here facilitate computation of decycling numbers of the squares of trees.
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    Some sufficient conditions for a planar graph of maximum degree four to be Class 1
    NI Wei-ping
    2010, 2010 (3):  85-91. 
    Abstract ( 3060 )   PDF (234KB) ( 1248 )   Save
    By applying discharging method, we showed that a planar graph G with maximum degree four and girth g is of class 1, if it satisfies one of the following conditions. (1) G does not contain cycles of length from 4 to 9; (2) G does not contain 4-cycles and 5-cycles, and two 3-faces are not incident with a common vertex; (3) G does not contain cycles of length from 5 to 8, and two 3-cycles, two 4-cycles are not incident with a common vertex ; (4) g≧geqslant 4, G does not contain chordal-8-cycle, and two 4-faces are not incident with a common vertex.
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    Multi-scale asymptotic solutions of multi-field coupled equations
    HOU Lei;ZHANG Jia-jian;Qiu Lin;
    2010, 2010 (3):  92-97. 
    Abstract ( 2816 )   PDF (294KB) ( 1366 )   Save
    This article described the complex fluid and the field constraints with gravitational effects.The asymptotic solution determines the dissipative equilibrium vector field of the coupled convection disturbance kinetic equations. For the analysis of the canonical and singular perturbation problems we analyze the micro-phenomena of the laboratory and macro-phenomena of nature.Our approach is to use the complex Fourier harmonic analysis, re-scale, and the introduction of new parameters to reduce the three-dimensional coupling dynamic equations into a one-dimensional complex space of boundary-layer. Two examples for the problem of the perturbation characteristic function were given with asymptotic analysis. Example 2 explains the turning point of the transition that from the index oscillation solution to the algebraic solution.
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    Asymptotic solutions of the nonlinear eigenvalue problems in the multi-fieldcoupled dynamic equations
    HOU Lei;;ZHANG Jia-jian;QIU Lin;
    2010, 2010 (3):  99-112. 
    Abstract ( 3098 )   PDF (314KB) ( 1144 )   Save
    This article solved the asymptotic solution of the eigenvalue problem in the
    dissipative equilibrium vector field of the coupled convection disturbance kinetic
    equations under the constraind filed and the gravity. The approach is to use the new parameters to reduce the three-dimensional coupling dynamic equations into a one-dimensional complex space of boundary-layer. Further analysis and computing were given on the asymptotic solutions for the nonlinear eigenvalue problem. Finally, a boundary-layer eigenvalue analysis was performed to solve the field coupling perturbation in this paper.
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    Existence and multiplicity of positive solutions to a class of singular third-order ordinary differential equations
    YAO Qing-liu
    2010, 2010 (3):  113-118. 
    Abstract ( 3219 )   PDF (335KB) ( 1312 )   Save
    The positive solutions were considered for a class of nonlinear third-order ordinary differential equations, where the nonlinear term contains first derivative of unknown function and may be singular in the term variable. The main conditions of the results are local. In other words, the equation may have 1-3 positive solutions provided the integrations of height functions of nonlinear term on some bounded sets are appropriate.
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    On existence of solutions to backward stochastic differential equation with generalized left-Lipschitz coefficients
    TIAN De-jian;JIANG Long;DENG Fang
    2010, 2010 (3):  119-125. 
    Abstract ( 3071 )   PDF (253KB) ( 1238 )   Save
    In this paper, we proved the existence of the solution to a backward stochastic differential equations (BSDE) with the generator satisfying the generalized left-Lipschitz condition. The key idea for dealing with the problem consists in constructing a monotonic sequence of solutions to BSDE and then passing to the
    limit. We construct a monotonic sequence of solutions by monotonic iteration technique. It is worth noting that the generator may be not continuous with respect to variable yand the varying of generator with respect to variables y and z may be not uniformly with respect to time parameter t.
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    The comparisons among credibility estimators under Esscher premium principle
    WANG Wei;WEN Li-min;ZHANG Yi
    2010, 2010 (3):  126-133. 
    Abstract ( 3243 )   PDF (294KB) ( 1653 )   Save
    This paper built the credibility model under Esscher premium principle, and derived the Bayes premium, Bayes estimator, credibility premium and credibility estimator of individual premium under Esscher premium principle correspondingly. In addition, the differences and connections among those estimators were compared, and the consistency were proved. Finally, the results were shown by simulations.
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    On the fluctuation spectra with respect to complex functions ofthe three-state Markov processes
    KUANG Neng-hui;CHEN Yong
    2010, 2010 (3):  134-142. 
    Abstract ( 2623 )   PDF (181KB) ( 1390 )   Save
    Explicit formulae for the autocorrelation functions and the fluctuation spectra with respect to complex functions of the irreducible three-state Markov processes were investigated. By the theory of cubic and quintic equations, the necessary and sufficient condition for the fluctuation spectra with respect to complex functions to be nonmonotonic on [0,+∞) was presented when there existed coinciding eigenvalues for the transition rate matrix, and the sufficient conditions for the fluctuation spectra with respect to complex functions to be nonmonotonic on [0,+∞)were given when there existed distinct nonzero eigenvalues.
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    Critical problems of totally isotropic subspaces in finite pseudo-symplectic spaces
    ZHAO Yan-bing;QIAN Guo-dong;HUO Yuan-ji
    2010, 2010 (3):  142-148. 
    Abstract ( 2776 )   PDF (254KB) ( 1332 )   Save
    With the properties and counting theorems of the finite
    pseudo-symplectic spaces, this paper studied the critical problems
    of totally isotropic subspaces in the finite pseudo-symplectic
    spaces and obtained the corresponding counting formulas and critical
    exponents
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