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    Majority Coloring of r-Regular Digraph
    XIA Wei-hao, SHI Mei, XIAO Ming-yue, CAI Jian-sheng, WANG Ji-hui
    Chinese Quarterly Journal of Mathematics    2022, 37 (2): 142-146.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.02.004
    Abstract179)      PDF(pc) (330KB)(93)       Save
     A majority k-coloring of a digraph D with k colors is an assignment c: V ( D ) →{ 1,2,···,k} , such that for every v∈V (D), we have c(w)=c(v) for at most half of all out-neighbors w∈N+( v ). For a natural number k≥2, a
    1/k-majority coloring of a digraph is a coloring of the vertices such that each vertex receives the same color as at
    most a 1/proportion of its out-neighbours. Kreutzer, Oum, Seymour, van der Zypen and
    Wood proved that every digraph has a majority 4-coloring and conjectured that every
    digraph admits a majority 3-coloring. Gir$\widetilde{a}$o, Kittipassorn and Popielarz proved that every
    digraph has a 1/k-majority 2k-coloring and conjectured that every digraph admits a
    1\k-majority (2k−1)-coloring. We showed that every r -regular digraph D with r>36ln(2n)
    has a majority 3-coloring and proved that every digraph D with minimum outdegree
    $\delta^+>\frac{2k^2(2k-1)^2}{(k-1)^2}\ln{[(2k-1)n]}$ has a 1/k-majority (2k−1)-coloring. And we also proved that
    every r-regular digraph D with  $r>\frac{3k^2(2k-1)}{(k-1)^2} \ln(2n)$ has a 1/k-majority (2k−1)-coloring.
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    Majorization and Fekete-Szegö Problems for Multivalent Meromorphic Functions Associated with the Mittag-Leffler Function
    LONG Pin-hong, GANGADHARAN Murugusundaramoorthy, HAN Hui-li, WANG Wen-shuai
    Chinese Quarterly Journal of Mathematics    2022, 37 (2): 111-123.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.02.001
    Abstract166)      PDF(pc) (356KB)(230)       Save
    The main object of this present paper is to investigate the problem of majorization of certain class of multivalent meromorphic functions of complex order involving Mittag-Leffler function. Meanwhile, for this subclass the corresponding coefficient estimates and some Fekete-Szeg¨ o type inequalities are obtained. Moreover we point out some new or known consequences of our main results.
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    The Conjugate Gradient Method in Random Variables
    HSU Ming-hsiu, LAI King-fai
    Chinese Quarterly Journal of Mathematics    2021, 36 (2): 111-121.   DOI: 10.13371/j.cnki.chin.q.j.m.2021.02.001
    Abstract153)      PDF(pc) (322KB)(194)       Save
    We study the conjugate gradient method for solving a system of linear
    equations with coefficients which are measurable functions and establish the rate of
    convergence of this method.
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    Global Existence and Uniqueness of Periodic Waves for a Perturbed Combined Double-Dispersive Equation
    LIAO Xiao-zhao, HUANG Wen-tao, YANG Su-min
    Chinese Quarterly Journal of Mathematics    2022, 37 (2): 124-131.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.02.002
    Abstract146)      PDF(pc) (534KB)(80)       Save
    In this paper, we study the periodic wave propagation phenomenon in elastic waveguides modeled by a combined double-dispersive partial differential equation (PDE). The traveling wave ansazt transforms the PDE model into a perturbed integrable ordinary differential equation (ODE). The global bifurcation theory is applied for the perturbed ODE model to establish the existence and uniqueness of the limit cycle, which corresponds
    the periodic traveling wave for the PDE model. The main tool is the Abelian integral taken from Poincar´ e bifurcation theory. Simulation is carried out to verify the theoretical result.
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    Painlev\'{e} Analysis of Higher Order Nonlinear Evolution Equations with Variable Coefficients

    Wang Yuan
    Chinese Quarterly Journal of Mathematics    2021, 36 (2): 196-203.   DOI: 10.13371/j.cnki.chin.q.j.m.2021.02.008
    Abstract144)      PDF(pc) (266KB)(190)       Save
    There is a close relationship between the Painlev´e integrability and other
    integrability of nonlinear evolution equation. By using the Weiss-Tabor-Carnevale (WTC)
    method and the symbolic computation of Maple, the Painlev´e test is used for the higher
    order generalized non-autonomous equation and the third order Korteweg-de Vries equation
    with variable coefficients. Finally the Painlev´e integrability condition of this equation is
    gotten.
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    Volume Inequalities for Sections and Projections of Asymmetric Convex Bodies
    CAO Zi-xin, Li Ai-jun
    Chinese Quarterly Journal of Mathematics    2022, 37 (2): 178-188.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.02.007
    Abstract142)      PDF(pc) (346KB)(75)       Save
    In this paper, we establish volume inequalities for k-dimensional sections and projections of convex bodies (not necessarily symmetric) and their polars in a more general position than John’s position.
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    Well-Posedness for Timoshenko System with Thermodiffusion Effects and Delay
    QIN Yu-ming, HAN Ning
    Chinese Quarterly Journal of Mathematics    2022, 37 (1): 1-9.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.01.001
    Abstract141)      PDF(pc) (293KB)(349)       Save
     In this paper, we study the well-posedness for the thermoelastic Timoshenko system with a constant delay and mass diffusion effects. Heat and mass exchange with the environment during thermodiffusion in Timoshenko beam. The C 0 -semigroup theory will be used to prove the well-posedness of the considered problem.
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    Induced Matching-Extendability of Halin Graphs
    ZHANG Qing-nan, HUI Zhi-hao, YANG Yu, WANG An,
    Chinese Quarterly Journal of Mathematics    2022, 37 (4): 380-385.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.04.005
    Abstract131)      PDF(pc) (344KB)(80)       Save
     Let G be a connected graph having a perfect matching. The graph G is said to be induced matching (IM) extendable if every induced matching M of G is contained in a perfect matching of G. In this paper, we show that Halin graph G =T ∪C is IMextendable if and only if its characteristic tree T is isomorphic to K1,3, K1,5, K1,7 or S2,2.
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    Blow-Up Result for a Semi-Linear Wave Equation with a Nonlinear Memory Term of Derivative Type
    OUYANG Bai-ping, XIAO Sheng-zhong
    Chinese Quarterly Journal of Mathematics    2021, 36 (3): 235-243.   DOI: 10.13371/j.cnki.chin.q.j.m.2021.03.002
    Abstract130)      PDF(pc) (330KB)(241)       Save
    In this paper, we study the blow-up of solutions to a semi-linear wave equation with a nonlinear memory term of derivative type. By using methods of an iteration argument and differential inequalities, we obtain the blow-up result for the semi-linear wave equation when the exponent of p is under certain conditions. Meanwhile, we derive an upper bound of the lifespan of solutions to the Cauchy problem for the semi-linear wave equation.
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    Exponential Growth of Solutions for Nonlinear Coupled Viscoelastic Wave Equations with Degenerate Nonlocal Damping and Source Terms
    LIU Shuo, ZHANG Hong-wei, Hu Qing-ying
    Chinese Quarterly Journal of Mathematics    2021, 36 (2): 210-220.   DOI: 10.13371/j.cnki.chin.q.j.m.2021.02.010
    Abstract122)      PDF(pc) (298KB)(192)       Save
    This paper is concerned with a system of nonlinear viscoelastic
    wave equations with degenerate nonlocal damping and memory terms. We will
    prove that the energy associated to the system is unbounded. In fact, it will
    be proved that the energy will grow up as an exponential function as time goes
    to infinity, provided that the initial data are positive initial energy.
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    EEG Feature Learning Model Based on Intrinsic Time-Scale Decomposition and Adaptive Huber Loss
    YANG Li-jun, JIANG Shu-yue, WEI Xiao-ge , XIAO Yun-hai
    Chinese Quarterly Journal of Mathematics    2022, 37 (3): 281-300.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.03.006
    Abstract122)      PDF(pc) (538KB)(316)       Save
    According to the World Health Organization, about 50 million people world-
    wide suffer from epilepsy. The detection and treatment of epilepsy face great challenges.
    Electroencephalogram (EEG) is a significant research object widely used in diagnosis and
    treatment of epilepsy. In this paper, an adaptive feature learning model for EEG signals
    is proposed, which combines Huber loss function with adaptive weight penalty term.
    Firstly, each EEG signal is decomposed by intrinsic time-scale decomposition. Secondly,
    the statistical index values are calculated from the instantaneous amplitude and frequency
    of every component and fed into the proposed model. Finally, the discriminative features
    learned by the proposed model are used to detect seizures. Our main innovation is to
    consider a highly flexible penalization based on Huber loss function, which can set different
    weights according to the influence of different features on epilepsy detection. Besides, the
    new model can be solved by proximal alternating direction multiplier method, which can
    effectively ensure the convergence of the algorithm. The performance of the proposed
    method is evaluated on three public EEG datasets provided by the Bonn University,
    Childrens Hospital Boston-Massachusetts Institute of Technology, and Neurological and
    Sleep Center at Hauz Khas, New Delhi(New Delhi Epilepsy data). The recognition
    accuracy on these two datasets is 98% and 99.05%, respectively, indicating the application
    value of the new model.
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    The Normal Family of Meromorphic Functions Concerning Shared Analytic Function
    YANG Qi, YUAN Wen-jun, TIAN Hong-gen
    Chinese Quarterly Journal of Mathematics    2022, 37 (1): 26-36.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.01.003
    Abstract122)      PDF(pc) (330KB)(136)       Save
    In this paper, we study the normal criterion of meromorphic functions concerning shared analytic function. We get some theorems concerning shared analytic function, which improves some earlier related results.
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    AOR Iterative Method for Coupled Lyapunov Matrix Equations
    ZHANG Shi-jun , WANG Shi-heng , WANG Ke
    Chinese Quarterly Journal of Mathematics    2021, 36 (2): 141-148.   DOI: 10.13371/j.cnki.chin.q.j.m.2021.02.003
    Abstract118)      PDF(pc) (285KB)(225)       Save
     An AOR (Accelerated Over-Relaxation) iterative method is suggested by
    introducing one more parameter than SOR (Successive Over-Relaxation) method for
    solving coupled Lyapunov matrix equations (CLMEs) that come from continuous-time
    Markovian jump linear systems. The proposed algorithm improves the convergence rate,
    which can be seen from the given illustrative examples. The comprehensive theoretical
    analysis of convergence and optimal parameter needs further investigation.
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    A Novel Parameter-Free Filled Function and Its Application in Least Square Method
    LI Shuo, SHANG You-lin, QU De-qiang,
    Chinese Quarterly Journal of Mathematics    2021, 36 (3): 263-274.   DOI: 10.13371/j.cnki.chin.q.j.m.2021.03.005
    Abstract117)      PDF(pc) (289KB)(132)       Save
    The filled function algorithm is an important method to solve global optimization problems. In this paper, a parameter-free filled function is proposed for solving general global optimization problem, discuss the theoretical properties of this function and give the corresponding algorithm. The numerical experiments on some typical test problems using the algorithm and the numerical results show that the algorithm is effective. Applying the filled function method to the parameter solving problem in the logical population growth model, and then can be effectively applied to Chinese population prediction. The experimental results show that the algorithm has good practicability in practical application.
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    The Polynomial Function Model in Born-Infeld Theory
    DAI Bing-bing, ZHANG Rui-feng
    Chinese Quarterly Journal of Mathematics    2022, 37 (3): 221-236.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.03.001
    Abstract117)      PDF(pc) (413KB)(88)       Save
     Based on the Lagrangian action density under Born-Infeld type dynamics and
    motivated by the one-dimensional prescribed mean curvature equation, we investigate the
    polynomial function model in Born-Infeld theory in this paper with the form of
    −([1−a(ϕ')2 ]ϕ' )' =λf(ϕ(x)),
    where λ> 0 is a real parameter, f ∈C2 (0 , + ∞ ) is a nonlinear function. We are interested
    in the exact number of positive solutions of the above nonlinear equation. We specifically
    develop for the problem combined with a careful analysis of a time-map method.
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    Finite Time Blowup with Upper Bound of Blowup Time of Solutions to Semilinear Parabolic Equations with General Nonlinearity
    LI Na, FANG Shao-mei
    Chinese Quarterly Journal of Mathematics    2022, 37 (1): 103-110.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.01.011
    Abstract114)      PDF(pc) (315KB)(162)       Save
    In this paper, we consider a semilinear parabolic equation with a general nonlinearity. We establish a new finite time blow-up criterion and also derive the upper bound for the blow-up time. The results partially generalize some recent ones obtained by He Ma et al.
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    Auslander Categories and Free Normalizing Extensions
    GU Qin-qin, ZHUO Yuan-fan
    Chinese Quarterly Journal of Mathematics    2021, 36 (2): 204-209.   DOI: 10.13371/j.cnki.chin.q.j.m.2021.02.009
    Abstract114)      PDF(pc) (299KB)(139)       Save
     Let RCS be a semidualizing (R,S)-bimodule. Then RCS induces an equivalent between the Auslander class AC (S) and the Bass class BC (R). Let A and B
    be free normalizing extensions of R and S respectively. In this paper, we prove that
    HomS(BBS,RCS) is a semidualizing (A,B)-bimodule under some suitable conditions,
    and so HomS(BBS,RCS) induces an equivalence between the Auslander class
    AHomS (BBS,RCS )(B)
    and the Bass class
    BHomS (BBS,RCS )(A).
    Furthermore, under a suitable condition on RCS, we develop a generalized Morita theory
    for Auslander categories
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    On the Eigenvalues and Eigenfunctions of the Sturm-Liouville Operator with the Barrier Potential
    SARWAR Qanitah, HUANG Zhen-you, ZAHID Abdul Hannan, XU Xin-Jian
    Chinese Quarterly Journal of Mathematics    2023, 38 (1): 50-61.   DOI: 10.13371/j.cnki.chin.q.j.m.2023.01.004
    Abstract112)      PDF(pc) (279KB)(131)       Save
    We aim to find the eigenvalues and eigenfunctions of the barrier potential
    case for Strum-Liouville operator on the finite interval [0 ,π ] when λ> 0. Generally, the
    eigenvalue problem for the Sturm-Liouville operator is often solved by using integral
    equations, which are sometimes complex to solve, and difficulties may arise in computing
    the boundary values. Considering the said complexity, we have successfully developed
    a technique to give the asymptotic formulae of the eigenvalue and the eigenfunction for
    Sturm-Liouville operator with barrier potential. The results are of significant interest in
    the field of quantum mechanics and atomic systems to observe discrete energy levels.
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    An Efficient Algorithm for Low Rank Matrix Restoration Problem with Unknown Noise Level
    JIN Zheng-fen, WANG Duo, SHANG You-lin, LV Jin-man
    Chinese Quarterly Journal of Mathematics    2021, 36 (4): 356-368.   DOI: 10.13371/j.cnki.chin.q.j.m.2021.04.002
    Abstract111)      PDF(pc) (363KB)(115)       Save
    Recovering an unknown high dimensional low rank matrix from a small set of entries is widely spread in the fields of machine learning, system identification and image restoration, etc. In many practical applications, the few observations are always corrupted by noise and the noise level is also unknown. A novel model with nuclear norm and square root type estimator has been proposed, which does not rely on the knowledge or on an estimation of the standard deviation of the noise. In this paper, we firstly reformulate the problem to an equivalent variable separated form by introducing an auxiliary variable. Then we propose an efficient alternating direction method of multipliers(ADMM) for solving it. Both of resulting subproblems admit an explicit solution, which makes our algorithm have a cheap computing. Finally, the numerical results show the benefits of the model and the efficiency of the proposed method.
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    Simplistic Universal Protocols for Remotely Preparing Arbitrary Equatorial States
    MA Song-ya LI Xiang, LI Qi
    Chinese Quarterly Journal of Mathematics    2022, 37 (3): 260-273.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.03.004
    Abstract108)      PDF(pc) (348KB)(135)       Save
     We first put forward a deterministic protocol to realize the remote preparation
    of arbitrary multi-qubit equatorial states via EPR pairs. A set of useful measurement
    basis is constructed which plays a key role. The receiver just needs to perform Pauli Z
    operations to recover the target state. Comparing with the previous protocols, the recovery
    operation is simplified and expressed by a general formula. As there are no universal
    protocols for high-dimensional systems, we further generalize to the case of multi-qudit
    equatorial states by means of Fourier transformation. It is worth mentioning that the
    proposed schemes can be extended to multi-party controlled remote state preparation.
    Moreover, we consider the effect of two-type decoherence noises.
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