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    25 May 2008, Volume 2008 Issue 3 Previous Issue    Next Issue
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    Article
    Approximation of C*-algebras by finite-dimensional quantized metric spaces(English)
    HUA Jia-jie
    2008, 2008 (3):  1-7. 
    Abstract ( 3298 )   PDF (208KB) ( 512 )   Save
    This paper proved that for a quantized metric space (A, L) coming from an action a of a compact group G on a C*-algebra A, there exists a sequence of finite-dimensional quantized metric spaces (An, L(n)) such that (A, L) is the limit of (An, L(n)) with respect to quantized Gromov-Hausdorff distance.
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    Relation between hereditarily indecomposable space and spaces with the ball-covering property(Chinese)
    LIN Li-hua
    2008, 2008 (3):  8-11. 
    Abstract ( 3293 )   PDF (324KB) ( 479 )   Save
    It was shown that if X is a hereditarily indecomposable Banach space, and Gateaux differentiability points are dense in X, then X is a ball-covering property space. And further if Gateaux differentiability points are dense in a infinitely dimensional subspace of X , then X is a ball-covering property space too.
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    Singularly perturbed BVP for third nonlinear ODE(Chinese)
    CHEN Li-hua;XU Jie;NI Ming-kang;
    2008, 2008 (3):  12-20. 
    Abstract ( 4002 )   PDF (574KB) ( 536 )   Save

    This paper studied a kind of BVP of nonlinear third order singularly perturbed equations by boundary layer function method. When gy′>0, at first, the problem was turned to a BVP of equivalent Tikhonov system. Then the asymptotic solution of doubly boundary layer for the system was constructed, and the character of exponential decay for all boundary functions was proved. Finally the main results of this paper: existence and uniqueness of solution and estimation of remainder for the problem are given. When gy′<0, in general, there is no solution to this problem.

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    Boundary value problem of a class of third order differential equations(Chinese)
    XU Jie;CHEN Li-hua;Ni Ming-kang;
    2008, 2008 (3):  21-29,3. 
    Abstract ( 3647 )   PDF (554KB) ( 442 )   Save
    This paper, using the method of boundary functions, studied boundary value problem of a class of singularly perturbed third order differential equations. At the same time the asymptotice solution of the problem was given and the uniform validity of its asymptotic solution was proved in a rigorous way.
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    Iterative algorithm for solving least Frobenius norm problem of an inconsistent matrix equation pair(English)
    XU Xiang-jian;WANG Ming-hui;WEI Mu-sheng
    2008, 2008 (3):  30-36. 
    Abstract ( 3493 )   PDF (410KB) ( 390 )   Save
    This paper presented an iterative algorithm for solving the least Frobenius norm problem of inconsistent matrix equation pair (AXB,CXD)=(E,F) with a real matrix X. By this algorithm, for any (special) initial matrix X0, a solution (the minimal Frobienius norm solution) can be obtained within finite iteration steps in the absence of roundoff errors. The numerical examples verify the efficiency of the algorithm.
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    Unicyclic subgraphs in 2-connected graphs(Chinese)
    LI Shi-yin;BAI Yun;DONG Qian;REN Han
    2008, 2008 (3):  37-44,1. 
    Abstract ( 4805 )   PDF (753KB) ( 638 )   Save
    This paper proved the following results:(1) The ⊙-graph of a 2-connected graph is 2(p-1) connected; (2) if a 2-connected graph G has two unicyclic spanning subgraphs and the number of one-valent vertices of these two subgraphs are respectively m and n (m<n), then for any integer k:m≦k≦n,there exist at least 2(p-1) unicyclic subgraphs of graph G whick have k one-valent vertices. Here, p is the dimension of the cycle space of G.
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    Some properties of the classification of states for Markov chains in random environment(Chinese)
    HUANG Zhen-sheng
    2008, 2008 (3):  45-50. 
    Abstract ( 3797 )   PDF (396KB) ( 681 )   Save
    Some basic concepts on the states, such as strongly recurrent state, weakly recurrent state, and strongly transient state, were proposed, and the corresponding Character number L(x,0;F) and G(x,0;F) were studied. On the base of this, Criteria for the states to be accesible and uniformly accesible were given. The results generalized the corresponding results in classical Markov chains.
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    I(x)-Reduced representations of generalized Jacobson-Witt algebras W(m;n)(English)
    LI Sha-sha;SHU Bin
    2008, 2008 (3):  51-58. 
    Abstract ( 3956 )   PDF (193KB) ( 642 )   Save
    This paper studied the representations of graded Cartan type Lie algebra W(m;n) in characteristic p>2, by generalizing the arguments of Shu's for restricted Lie algebras W(m;1). Especially, the rank-reducing method exploited in the restricted case was extended to non-restricted case. The simple
    modules for W(m;n) with generalized p-character x were described by reduction when x was regular semisimple.
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    Comparison theorems of stochastic difference equations(English)
    WANG Ting;GUO Xiao-lin;YANG Sheng-wu
    2008, 2008 (3):  59-66. 
    Abstract ( 4435 )   PDF (172KB) ( 777 )   Save

    This paper studied a kind of nonlinear stochastic difference equations, whose randomness is driven by a stochastic series. Two comparison theorems were obtained. At last, p-moment stability and p-moment boundedness of solutions to stochastic difference equations were presented as applications of obtained comparison theorems.

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    Estimate of bounds for the eigenvalue of Hadamard product of an M-matrix and its inverse(Chinese)
    Huang Rong
    2008, 2008 (3):  67-74. 
    Abstract ( 3258 )   PDF (218KB) ( 419 )   Save
    Let A be a strictly block diagonally dominant matrix, the norms for blocks of its inverse were estimated. Furthermore, if A is an M-matrix, we gave a new bounds of the minimum eigenvalue of AoA-1, and proved that the bounds are less than 2/n.
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    Complexity analysis of time series generated by elementary cellular automaton of Rule 7(Chinese)
    QIN Da-kang;JIANG Zhi-song
    2008, 2008 (3):  75-82. 
    Abstract ( 3310 )   PDF (652KB) ( 522 )   Save

    Using the tools of distinct excluded blocks, computational search and symbolic dynamics, the complexity of the times series generated by elementary cellular automaton of Rule 7 was analyzed, the set of distinct excluded blocks and its Chomsky hierarchy and the Chomsky hierarchy of a reduction of the evolution language were determined.Finally,the mathematical structure underlying the time series was obtained.

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    Automatic recognition and translation of english address on postal mails(Chinese)
    TU Xiao;CHEN Guo-yue;LU Yue
    2008, 2008 (3):  83-91. 
    Abstract ( 5087 )   PDF (764KB) ( 606 )   Save

    According to the characteristics of the language used in address, rules different from those of natural languages were defined and applied to automatically recognize and translate English address on postal mails. To deal with the address got from Optical Character Recognition, an English-to-Chinese address translation method based on inexact string matching technology was proposed to recognize English address and translate it into Chinese. The experimental results showed that the present method is capable of reducing the influence of OCR error, and improving the translation performance.

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    Ray tracing method based on a virtual source tree(Chinese)
    LIAO Bin;ZHAO Ni-li;ZHU Shou-zheng
    2008, 2008 (3):  103-108. 
    Abstract ( 3560 )   PDF (547KB) ( 476 )   Save

    An effective ray tracing method based on virtual source tree for prediction of indoor radio propagation was presented in this paper. The data of transmiting source, reflection source, diffraction source and receiving point were stored with many-fork tree in Delphi, and the validity of the nodes of the tree was estimated, to make the ray tracing course more simple and efficient. It was found that the predicted results with the method are in good agreement with the simulated results in FDTD, and the validity of the method is also verified by the experimental test.

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    Judd-Ofelt theory analysis and calculation(Chinese)
    LIN Liang-shu;XUE Yan-ling;JIANG Qi-cheng
    2008, 2008 (3):  109-114. 
    Abstract ( 6051 )   PDF (535KB) ( 984 )   Save

    A clear presentation of the formulas and parameters in the Judd-Ofelt theory was given. Three intensity parameters was calculuted by the least-squares fitting method. Consequently, the algorithms of calculating the Judd-Ofelt parameters such as the oscillator strength, the spontaneous emission probability, branching ratio and radiative lifetime were discussed. Especially, three tables were given to make the complex algorithms be easily understood.

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    Generation of SO molecular beam by pulsed DC discharge:A'3→X3-ransition(Chinese)
    DU Wei-di;LI Chuan-liang;CHEN Yang-qin;YANG Xiao-hua
    2008, 2008 (3):  115-119. 
    Abstract ( 3210 )   PDF (448KB) ( 543 )   Save
    The sulfur oxide radical (SO) molecular beam was generated by DC pulsed discharging the SO2 seeded in helium with the ratio of 1:99 at total pressure of 3.0×105 Pa in the supersonic expansion. The emission spectrum in the range of 350-500 nm was assigned to the A'3→X3- system of SO. The generation of SO free radical was interpreted to be Penning ionized from its precursor SO2 then further dissociated. Analyzing the medium resolution SO vibronic spectra, the molecular constants of the states of SO involved in the transition are determined to be ν00 = 29524(8) cm-1, ω''e = 1165(5) cm-1, ω''eχ''e = 6.4(0.5) cm-1, ω'e = 742(6) cm-1, ω'eχ'e = 5.9(2.0) cm-1.
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    Influence of Joule annealing on GMI effect for Co-based amorphous microwires(Chinese)
    YUAN Li;YANG Xie-long;ZHAO Zhen-jie
    2008, 2008 (3):  120-124. 
    Abstract ( 3235 )   PDF (464KB) ( 545 )   Save

    Co-based(Co69.20Fe4.16 Si12.35B10.77 Cr3.42 Mo0.1) amorphous microwires with 40 μm in diameter and 5 cm in length,were annealed by Joule current and by stress Joule annealing. The relationship between giant magneto-impedance effect and the density of annealing current and the intensity of stress was investigated. The results showde that the GMI ratios firstly increase then decrease with the increase of the density of current and the intensity of the stress. The maximum of sensitivity of GMI ratios to applied field is 1%/( A·m-1) at 20 A/mm2 and 90 MPa.The sensitivity of wires which were annealed with these conditions can be 19%/(A·m-1).

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