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    25 May 2007, Volume 2007 Issue 3 Previous Issue    Next Issue
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    Article
    Application of Boundary Layer Function Method in Differential Inequality(Chinese)
    NI Ming-kang;;LIN Wu-zhong;
    2007, 2007 (3):  1-10. 
    Abstract ( 3444 )   PDF (547KB) ( 544 )   Save
    This paper discussed a kind of singularly perturbed ODE with boundary value. The upper and lower solutions defined in Nagumo Theorem by means of Vasil’eva’s boundary layer function method were contructed. Actually, it is of great universality and easy to use. After the construction, the existence of the solution of this singularly perturbed problem and estimation of the remainder terms with differential estimation of inequalities
    was proved.
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    Algebraic Perturbation Theory for Some Generalized Inverse(Chinese)
    SHENG Xing-ping;CHEN Guo-liang
    2007, 2007 (3):  11-15. 
    Abstract ( 3019 )   PDF (316KB) ( 493 )   Save
    This paper introduced several properties of α-β generalized inverse, then used these properties to discuss the algebraic perturbation theory for the α-β generalized inverse in three kinds. The expression of the algebraic perturbation of α-β generalized inverse were presented.This paper introduced several properties of α-β generalized inverse, then used these properties to discuss the algebraic perturbation theory for the α-β generalized inverse in three kinds. The expression of the algebraic perturbation of α-β generalized inverse were presented.
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    Invariant Solutions of Gauss Equation on Jet Bundle R3(Chinese)
    HE Mei;
    2007, 2007 (3):  16-22. 
    Abstract ( 3075 )   Save
    Using symmetry group methods, this paper studied the invariant groups admitted by Gauss curvature equation on jet bundle R3. Invariant groups, infinitesimal generators of the corresponding invariant groups and some group-invariant solutions were found. Results about some surfaces which have constant Gauss curvature were given.
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    Nonlinear Stability of Three-Dimensional Quasi-Geostrophic Motions in Spherical Geometry(English)
    CAI Jing-jing;LIU Yong-ming;
    2007, 2007 (3):  23-30. 
    Abstract ( 3558 )   Save
    A nonlinear stability theorem was established for three-dimensional quasi-geostrophic motions in spherical geometry by establishing an optimal Poincaré inequality. The inequality was derived by variational principle.
    The result was shown better than the known results. Moreover, explicit upper bounds for the disturbance energy, the disturbance potential enstrophy, and the disturbance boundary energy on the rigid lids were also established.
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    Stability in Terms of Two Measures with Perturbing Lyapunov Functions(English)
    GENG Feng-jie
    2007, 2007 (3):  31-38. 
    Abstract ( 2891 )   Save
    This paper extended the method of perturbing cone-valued Lyapunov functions for a system of difference equations. Some properties of $(h_0,h)$-stability and $(h_0,h)$-asymptotical stability were discussed under much weaker assumptions.
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    Oscillations of Certain Second-Order Nonlinear Differential Equations with Impulses(English)
    ZHANG Wei-peng;BI Ping;ZHU De-ming
    2007, 2007 (3):  39-48. 
    Abstract ( 3073 )   Save
    This paper considered the oscillatory behavior of solutions of a second-order impulsive ordinary differential equation by using impulsive differential inequalities established by Lakshmikantham et al. Sufficient conditions were obtained for all solutions of this type of equations to be oscillatory, illustrating that impulses play an important role in giving rise to the oscillation of equations. In particular, our work generalizes some known results. Finally, an example was presented to explain the key role of impulses in
    generating oscillatory.
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    Strong and Weak Convergences of Implicit Iteration Process for Some Asymptotically Nonexpansive Mappings(English)
    QUAN Jing;ZHANG Shi-sheng;LONG Xian-jun
    2007, 2007 (3):  49-57. 
    Abstract ( 3231 )   Save

    The purpose of this paper was to prove some strong and weak convergence theorems of the modified implicit iteration sequence to a common fixed point for a finite family of asymptotically nonexpansive mappings in Banach spaces. The results presented here improve many recent works.

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    Custom Building Finite Tight Frames(Chinese)
    XIN You-ming
    2007, 2007 (3):  58-61. 
    Abstract ( 3062 )   Save
    Let {φm} m=1M be not all zeros vectors of CN. This paper introduced an algorithm to construct a tight finite frame by adding N-d1vectors to{φm} m=1M, where d1 is determined by {φm} m=1M.
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    Crossing Number of C(3m,m)(Chinese)
    LIN Shao-qin;XU Tu;REN Han
    2007, 2007 (3):  62-66. 
    Abstract ( 3287 )   Save
    Using surgical operations on graphs and induction method, this paper proved that the crossing number of the circular graph C(3m,m) is m.
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    Largest Spectral Radius among Graphs with k Cut Edge(Chinese)
    WU Ya-rong;HE Sha;SHU Jin-long
    2007, 2007 (3):  67-74. 
    Abstract ( 3162 )   Save
    This paper showed the types of graphs with the largest spectral radius and the second largest spectral radius among all the graphs with k cut edges respectively.
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    On the Spectral Radius of Trees with Fixed Maximal Degree(Chinese)
    XU Qin;LIN Qi;SHU Jin-long
    2007, 2007 (3):  75-81. 
    Abstract ( 3659 )   Save
    This paper discussed the spectral radius of trees with fixed number of vertices and fixed maximal degree,\ and gave the upper bound and lower bound of the spectral radius of those trees respectively. Furthermore, the minimal spectral radius were obtained at trees $T’_\Delta, T_\Delta $ and $T_\Delta^*$.
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    Predictive Control of Networked Systems with Data Packed(Chinese)
    LENG Cui-ping;ZHENG Yu-fan;ZHANG Xiao-mei
    2007, 2007 (3):  82-88. 
    Abstract ( 3592 )   Save
    A new protocol of network data transmission (i.e. input and output data are packed before transmission) was adopted. Under this protocol, the design of the predictive controller and stability analysis of the networked system were studied. It was proved that the design of the observer and the state feedback controller of the augmented system satisfied separation principle. The responding controller was given in terms of LMIs. A numerical example was provided to show the effectiveness of the method
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    Dircect Method for Solving Burgers Equation(Chinese)
    XI Yuan-xi
    2007, 2007 (3):  89-92. 
    Abstract ( 3695 )   Save
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    Intelligent Algorithm in Image Enhancement Technology (Chinese)
    SONG Juan;QUAN Hui-yun
    2007, 2007 (3):  93-99. 
    Abstract ( 3536 )   Save
    This paper proposed a novel cooperative evolutionary algorithm based on
    simulated annealing algorithm(SA)and particle swarm optimization(PSO). This new method utilizes the global convergence property of SA and the
    facility of realization of PSO, and attains an optimal solution by means of
    the information exchanges of these two kinds of algorithms. Results of
    experiments showed that the proposed algorithm performs better in
    convergence speed and precision of solutions than GA,PSO and SA.

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    Segmentation Algorithm Based on Subpixel Image (Chinese)
    HAN Wen-wen;WANG Ling;CHEN You-guang
    2007, 2007 (3):  100-106. 
    Abstract ( 3236 )   Save
    An algorithm was proposed to realize image segmentation with subpixel
    image based on Niblack and Otsu algorithms. Experimental results showed
    that the proposed algorithm can keep the characters′ topological structure,
    and yield smooth edge effectively. Compared with the original image
    segmentation, this proposed method is more efficient.
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    Infrared Electro Optical Property of Holographic Polymer Dispersed Liquid Crystal Grating (Chinese)
    XIN Zhao-hui;CAI Ji-guang;SHEN Guo-tu;YANG Bao-cheng;ZHENG Ji-hong;GU Ling-juan
    2007, 2007 (3):  107-113. 
    Abstract ( 3147 )   Save
    Experiments were performed to research the electrooptical characteristics of holographic polymer dispersed liquid crystal (HPDLC) at 1 550 nm. Results showed that the frequency and amplitude of the applied field impact the
    diffraction efficiency and transmission efficiency of HPDLC greatly. The theory
    of dielectric matters was used to explain the relationship between the
    applied field frequency and the dielectric constant and how it influences the
    effect of electrooptical modulation of the HPDLC. It was proved that the HPDLC devices are potentially useful for Erbium doped fiber amplifiers as a
    tunable gain equalizer.
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    Ab Initio Calculation of CN Free Radical Using MRD-CI (Chinese)
    YANG Ming;GUO Ying-chun;YANG Xiao-hua;CHEN Yang-qin
    2007, 2007 (3):  114-118. 
    Abstract ( 3080 )   Save
    Ab initio MRD-CI calculations were carried out for the low lying states of CN. The potential curves for the X2Σ+ ground state and A2Π+ excited state were determined. The bond lengths of the two states were found to be in good agreement with the experimental results. The spectroscopic constants of the two states were obtained by solving the Schodinger equation with the obtained potential energy. And the rotational constants′ first three digits are found significant after comparing with the experimental values.
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    Capacitive Deionization with Carbon Nanotubes Film Electrodes (Chinese)
    WANG Xin-zheng;PAN Li-kun;LI Mao-gang;CHEN Yi-wei;CHENG Rong-ming;HUANG Su-mei;SUN Zhuo
    2007, 2007 (3):  119-126. 
    Abstract ( 3565 )   Save
    Carbon nanotubes (CNTs) films electrodes were fabricated by low pressure
    and low temperature thermal chemical vapor deposition (CVD) for capacitive
    deionization (CDI) application. The CNTs films were mainly composed of
    mesopores (2~50 nm) and a small portion of macropores (>50 nm). The pore
    size distribution was optimal for CDI application. The CDI capacity was also
    dependent on working parameters: Higher ions removal is achieved with
    higher applied voltage and an optimal flow rate. The CDI capacity is
    dependent on ions properties: monovalent ions with smaller hydrated radii
    are preferentially removed from water.
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    Research on Electrical Composites: Multiwalled Carbon Nanotube/Sulfonated Polyphenylacetylene(Chinese)
    BIAN Cheng-xiang;XU Xue-cheng;YANG Guo-guang
    2007, 2007 (3):  127-134. 
    Abstract ( 3579 )   Save
    CompositesSulfonated Polyphenylacetylene/Multiwalled Carbon Nanotube(SPPA/MWNT)were prepared by mixing SPPA with MWNT under ultrasonic bath. The composites were studied using Fourprobe, X-Ray photoelectron Spectroscope, UV-Vis-NIR spectrophotometer, X-Ray diffraction, Field Emission Scanning Electron Microscope (FESEM) ,etc. The results show strong interactions between MWNT and SPPA as well as a behavior of
    Negative Temperature Coefficient (NTC) of resistance. The phenomenon of
    the low percolation threshold and twice obvious increases of electrical
    conductivity were also found in the composites. It is assumed that SPPA with
    higher electrical conductivity due to charge transfer between SPPA and MWNT,which were affected by interaction, contacts with each other. Thus it forms
    conductive networks in the composites.
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    Excellent Characteristics of ZnO Nanowires Synthesized by Two Step Method (Chinese)
    ZHANG Qiu-xiang;ZHANG Yong-sheng;BAI Wei;YU Ke;ZHU Zi-qiang
    2007, 2007 (3):  135-140. 
    Abstract ( 2985 )   Save
    ZnO nanowires with excellent properties were synthesized by twostep method. Photoluminescence (PL) measurements showed that the ZnO nanowires
    have stronger ultraviolet emission properties at 376 nm and there is a
    5 nm blue shift after being immersed in thiourea (TU) solution compared with those of without immersion. The immersed ZnO nanowires show a turnon field of 2.3 V/μm at a current density of 0.1 μA/cm2 and emission current density up to 1 mA/cm2 at an applied field of 6.8 V/μm, which are 2.7 V/μm and 7.9 V/μm for those of without being immersed, respectively.
    So this method may be an effective method to improve the characteristics
    of ZnO nanowires.
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