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    25 January 2007, Volume 2007 Issue 1 Previous Issue    Next Issue
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    Article
    Image and Simple Form of a Derivation on a Banach Algebra(Chinese)
    LIU Jun-Ping
    2007, 2007 (1):  1-6. 
    Abstract ( 2666 )   Save
    This paper proved Vukman's conjecture concerning the image of a linear derivation on a Banach algebra, gave some sufficient conditions that the image of a linear derivation on complex Banach algebra was in the Jacobson radical, and also discussed the simpleorm of a linear derivation on an annihilator Banach algebra.
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    Eigenvalue Problems for Second-order Dynamic Equations on Time Scales(English)
    GENG Feng-jie;ZHU De-ming
    2007, 2007 (1):  7-12. 
    Abstract ( 3043 )   Save
    The paper studied the eigenvalue problems for nonlinear second-order dynamic equations on time scales with m-point boundary conditions. Using Schauder's
    and Krasnoselskii's fixed point theorems, the eigenvalues were characterized and the existence of positive solutions established. Several kinds of intervals of
    λ were presented explicitly, in which the existence of at least one positive solution of BVP was guaranteed.
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    Oscillation Criteria for Certain Nonlinear Matrix Differential Equations with Damping(English)
    XU Yan-cong;MENG Fan-wei
    2007, 2007 (1):  19-26. 
    Abstract ( 3327 )   Save
    Using the method of integral average technique and defining a new prepared solution, this paper presented some new oscillation criteria of matrix differential equations with damping, which extend the results of Rogovchenko and Li for scalar cases and improve the results of Yang for matrix cases; a few examples was given at the end.
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    Periodicity of a Nonautonomous Ratio-Dependent Predator-Prey Systems with Impulses(English)
    ZHANG Wei-peng;ZHU De-ming
    2007, 2007 (1):  27-35. 
    Abstract ( 2850 )   Save
    This paper explored the existence of periodic solutions with strictly positive components and impulses of a nonautonomous ratio-dependent predator-prey system. Sufficient criteria were obtained for the existence of strictly positive periodic solutions. The approach was based on a continuation theorem in the coincidence degree theory as well as some prior estimates.
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    New Definitions of Partial Ordering of Generalized Inverse(Chinese)
    HUANG Xuan-chen;WEI Mu-sheng
    2007, 2007 (1):  36-41. 
    Abstract ( 3415 )   Save
    By using the concept of partial ordering of matrix, some new definitions of partial ordering were put forward, such as $\boldsymbol{A}\leqslant^{\{1\}}\boldsymbol{B}\Leftrightarrow \boldsymbol{A}\boldsymbol{A}\{1\}=\boldsymbol{B}\boldsymbol{A}\{1\},\boldsymbol{A}\{1\}\boldsymbol{A}=\boldsymbol{A}\{1\}\boldsymbol{B} $ and $\boldsymbol{A}\leqslant^{\{1,2\}}\boldsymbol{B}\Leftrightarrow \boldsymbol{A}\boldsymbol{A}\{1,2\}=\boldsymbol{B}\boldsymbol{A}\{1,2\},\boldsymbol{A}\{1,2\}\boldsymbol{A}=\boldsymbol{A}\{1,2\}\boldsymbol{B}$. Four situations were discussed in detail, according to which, sufficient and necessary conditions of the new partial ordering have been derived.
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    Global Robust Control for a Class of Singularly Perturbed Systems with Nonlinear Uncertainties(Chinese)
    WANG Ge-xia;CHEN Kun;WANG Zhi-ming
    2007, 2007 (1):  42-46. 
    Abstract ( 2985 )   Save
    The global robust stabilization problem for a class of
    nonlinear uncertain two-time scale systems was studied. The robust
    composite feedback control for the whole systems was obtained by
    applying the two-time scale design approach, and the upper stability
    bound of $\varepsilon $ was also given. Finally, examples of the
    application of the result were presented.
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    Stability Criterion for Nonlinear Time-Varying Discrete-time Systems(Chinese)
    YU Su-juan;WANG Zhi-ming
    2007, 2007 (1):  47-50. 
    Abstract ( 3955 )   Save
    The asymptotic stability of nonlinear time-varying discrete-time systems was studied by using Lyapunov approach. If there exists time independent Lyapunov function V that is positively definite, and its difference is non-increased along the solutions of the systems, plus the additional condition imposed as the one of statements of the Barbashin-Krasovskii theorem, the
    conclusion of asymptotic stability will be obtained. In applications of Theorem 1 to the time-invariant and periodic systems respectively, the LaSalle theorem and Barbashin-Krasovskii theorem can be reobtained.
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    Approximation Algorithm for the Total Tardiness Scheduling(Chinese)
    ZHANG Shu-xia;TANG Guo-chun
    2007, 2007 (1):  51-55. 
    Abstract ( 2771 )   Save
    For the total tardiness scheduling with precedence constraints, an approximation algorithm with polynomial complexity was presented by
    transplanting the backward-shift algorithm of the case without precedence constraints. The new algorithm can get an approximation solution for the scheduling quickly.
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    Choice Number of Some Complete Multi-partite Graphs(English)
    XU Yang;
    2007, 2007 (1):  56-61. 
    Abstract ( 2793 )   Save
    This paper investigated the choice number of some complete k-partite graphs, pointed out and corrected some mistakes of S. Gravier, H. Enomoto, et al.. The choice number of the complete k-partite graph K(4, 2, ..., 2) were determined, and also presented were a type of complete multi-partite graphs whose choice numbers are not equal to their chromatic numbers.
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    Number of 0-1 Triangles in Edge-Coloring of Complete Graphs(Chinese)
    ZHANG Yan;REN Han
    2007, 2007 (1):  62-64. 
    Abstract ( 2977 )   Save
    This paper studied the lower bound for the number of triangles having the same color in any 2-edge-colored complete graph, and found the exact number of such triangles by means of adjacency matrix.
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    Robustness of GLSE(Chinese)
    LIU Xiang-rong;WANG Jing-long
    2007, 2007 (1):  65-69. 
    Abstract ( 3662 )   Save
    Linear regression model with elliptically symmetric errors and unknown dispersion matrix was discussed. For a given matrix $ \Sigma}_{0}$, when the real dispersion matrix varying within certain range, the GLSE $\hat{\beta}({\vec \Sigma}_{0}) = (\X'{\vec \Sigma}_{0}^{-1}\X)^{-1}\X'{\vec \Sigma}_{0}^{-1}y$ is the minimum risk estimator under a large class of loss functions, which implies the GLSE is a robust estimator with respect to dispersion matrix and loss functions.
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    Upper Bound for Renewal Risk Model with Stochastic Investment Return(English)
    XU Lin;WANG Rong-ming;YAO Ding-jun
    2007, 2007 (1):  70-77. 
    Abstract ( 2915 )   Save
    Ruin problems in the ordinary renewal risk model with stochastic investment were examined. The asset price process of investment is denoted by $\{e^{R_t},\ t\geqslant 0\}$, where $R_t$ is assumed to be a L\'{e}vy process. By constructing a supermartingale associated with the ruin time of the surplus process with investment, an upper bound for ultimate ruin probability by
    martingale approach was presented. The impact of inter-arrival times of claims on ruin probability was considered by numerical method.
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    Online Expressions of Scientific Formula(Chinese)
    YE Chang-qing;WANG Zhen-xing
    2007, 2007 (1):  78-83. 
    Abstract ( 2911 )   Save
    This paper designed a WYSWYG online formula input system based on MathML, in order to transmit and present the scientific formula in plain text on the network.
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    Method on StructureBased Fingerprint Feature Extraction (Chinese)
    XU Yang;ZHANG Xuedong
    2007, 2007 (1):  84-90. 
    Abstract ( 3090 )   Save
    The algorithm of fingerprint feature extraction using Gabor filterbank was
    proposed in order to overcome the drawback of traditional minutiae feature
    extraction. Through studying texture structure information of fingerprint ridges
    and applying Gabor filterbank to texture, a physical model of Gabor filtering
    was established. A quick and simple method of center point searching was
    presented, according to center point's position round grid feature area was
    located, filtering by eight directions of Gabor filterbank and feature extraction.
    The result of comparison experiment showed validity of Gaborbased.
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    Simulation Model for the Order-Inventory-Sale Policy of a Kind of Merchandise(Chinese)
    DAI Shu-gui;JIANG Chang-hua;PAN Yin-rong;HU You-hua
    2007, 2007 (1):  91-99. 
    Abstract ( 3547 )   Save
    Merchandise with certain lifespan and orderdiscount was studied. Its characters in orderinventorysale were analyzed. Based on the simulation principle of the discrete events system, a system simulation model was created, and the simulation software was developed. The inventory system was analyzed with simulation experiments. The model and the software supply retailers with an efficient tool for establishing orderinventorysale policy.
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    Analysis and Improvement of SVDBased Image Watermarking Algorithm(Chinese)
    LI Bin;WANG Xin-wei
    2007, 2007 (1):  100-106. 
    Abstract ( 3465 )   Save
    This paper analyzed some existing image watermarking algorithms using
    singular value decomposition(SVD) technique, and pointed out they have the problem of high error detection rate of original image and randomly chosen images. With the analysis of SVD's properties a new algorithm was proposed. Experiments showed the new proposed algorithm can distinguish the watermarked image from unwatemarked original image.It can also
    significantly decrease error detection rate of randomly chosen images.
    This algorithm has good robustness.
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    Influence of Metallic Core Diameter on Giant Magnetoimpedance Effect for Fe-based Nanocrystalline Microwires (Chinese)
    ZHANG Jun-che;LIU Long-ping;ZHAO Zhen-jie;YANG Xie-long;WANG Qing-jiang
    2007, 2007 (1):  107-112. 
    Abstract ( 3262 )   Save
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    Mechanism of Interface Reaction and Magnetic Properties of Fe-TiN Prepared by High Energy Ball Milling (Chinese)
    ZHOU Xiong-tu;JIANG Dong-mei;MA Xue-ming;SHI Wang-zhou
    2007, 2007 (1):  113-118. 
    Abstract ( 2976 )   Save
    Mechanism of interface reaction and magnetic properties of Fe-TiN system attained by high energy ball milling were studied using Xray diffraction (XRD), Mssbauer spectroscopy and vibrating sample magnetometer(VSM). The results showed that during ball milling, a small amount of Fe atoms diffuse
    into the interface of TiN grains to form a paramagnetic interface phase TiN(Fe)and the diffusion of Fe atoms saturates with increasing milling time. Meanwhile, Ti and N atoms, as a result of the decomposition of fractional TiN,
    dissolve into the crystal lattices of Fe to form a ferromagnetic solid solution of
    Fe (Ti,N). The solid solution of Ti and N atoms make the saturation magnetization
    of powder samples rise first and then fall with the amount of Ti and N atoms increasing.
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    Separation of Various Components of Nonstationary Signal Using Half Fourier Transform (Chinese)
    YAO Hong-yu;LIU Yue-qian
    2007, 2007 (1):  119-126. 
    Abstract ( 2880 )   Save
    This paper used the Half Fourier Transform to analyze various components of
    a nonstationary signal. By MATLAB simulation, a practical example, remote
    sensing a finite cylinder, was tested to verify the proposed algorithm. The
    result showed that in the higher SNR, the proposed algorithm can perfectly
    meet our expectation: to separate impulse like components from damped exponentials.
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    Study on Giant MagnetoImpedance Effect in Ni80Fe20Composite Multilayers (Chinese)
    SONG Zi-cheng;YUAN Wang-zhi;ZHAO Zhen-jie;RUAN Jian-zhong;YANG Xie-long
    2007, 2007 (1):  127-134. 
    Abstract ( 2984 )   Save
    The(Ni80Fe20/SiO2)n/Cu/(SiO2/Ni80Fe20)n composite multilayers were deposited onto glass substrates using RF magnetron sputtering equipment. The giant magneto impedance (GMI) effect was been investigated. The results show that the GMI effect enhanced, when the (Ni80Fe20/SiO2) bilayers structure repeated in the sample. At n=3, the maximum LMI ratio is 10.81%,while the maximum TMI ratios is 17.08%. And when n increases to 4 and 5, the MI ratios decrease slightly compared with the ratios at n=3. By the Xray diffraction spectrums and the hysteresis loops, the change of the
    samples′ crystallization structure, magnetism characteristic and GMI effect
    were studied, which were induced by the number of bilayers.
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    Preparation of Rutile Titania Nanoparticles at Low Temperature (Chinese)
    DONG Rui;JIANG Ji-sen
    2007, 2007 (1):  135-140. 
    Abstract ( 3066 )   Save
    This paper reported a novel method to prepare rutile TiO2 nanoparticles. When TiCl4 solution hydrolyzed, rutile TiO2 nanoparticles can be prepared
    at low temperature by adding a kind of organic additive into TiCl4 solution.
    XRD, FE-SEM and TG-DTA were used to analyze the influence of the amount of organic additives and the calcining temperature on the phase and particle
    size of prepared nanoparticles. It was found that the best additive amount is
    0.5 g/100 mL H2O, and the best calcining temperature is about 400 ℃. Being treated at the best condition, rutile TiO2 nanoparticles (40~50 nm) can be obtained.
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