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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
    Abstract156)      PDF(pc) (538KB)(393)       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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    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
    Abstract252)      PDF(pc) (330KB)(387)       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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    Complexity on Proximal Quasi-Newton Methods for a Class of Nonconvex Composite Optimization
    JIN Ling-Zi
    Chinese Quarterly Journal of Mathematics    2023, 38 (1): 62-84.   DOI: 10.13371/j.cnki.chin.q.j.m.2023.01.005
    Abstract154)      PDF(pc) (404KB)(277)       Save
    This paper studies a class of nonconvex composite optimization, whose
    objective is a summation of an average of nonconvex (weakly) smooth functions and a
    convex nonsmooth function, where the gradient of the former function has the Hölder
    continuity. By exploring the structure of such kind of problems, we first propose a
    proximal (quasi-)Newton algorithm wPQN (Proximal quasi-Newton algorithm for weakly
    smooth optimization) and investigate its theoretical complexities to find an approximate
    solution. Then we propose a stochastic variant algorithm wPSQN (Proximal stochastic
    quasi-Newton algorithm for weakly smooth optimization), which allows a random subset
    of component functions to be used at each iteration. Moreover, motivated by recent
    success of variance reduction techniques, we propose two variance reduced algorithms,
    wPSQN-SVRG and wPSQN-SARAH, and investigate their computational complexity
    separately.
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    Dynamic Analysis of a Predator-Prey Model with State-Dependent Impulsive Effects
    LI Yong-feng, ZHU Cheng-zhi, LIU Yan-wei
    Chinese Quarterly Journal of Mathematics    2023, 38 (1): 1-19.   DOI: 10.13371/j.cnki.chin.q.j.m.2023.01.001
    Abstract141)      PDF(pc) (2367KB)(270)       Save
     In this paper, a pest-dependent model and integrated pest management
    strategy is proposed, that is, when pest populations reach levels that impair economic
    development, we will use a combination of strategies, such as biological, cultural and
    chemical control strategies reduce pests to a reasonable level. First, we investigated the
    system without control measures, and discussed the existence and stability of equilibria,
    we also proved the system has no limit cycle. Then, a state feedback impulsive model is
    constructed, the existence and uniqueness of the order-one periodic solution are proved
    by means of the successor function method to confirm the feasibility of the biological and
    chemical control strategy of pest management. Secondly, the stability of system is proved
    by the analogue of the Poincar ´ e criterion. Finally, we give an example and numerical
    simulations to explain the mathematical conclusions.
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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
    Abstract245)      PDF(pc) (356KB)(264)       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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    Space-Time Legendre Spectral Collocation Methods for Korteweg-de Vries Equation
    WANG Chuan, QIAO Yan
    Chinese Quarterly Journal of Mathematics   
    Accepted: 12 April 2023

    Stability and Hopf Bifurcation of an Eco-Epidemiological Model with Delay
    BAI Hong-fang
    Chinese Quarterly Journal of Mathematics    2023, 38 (2): 157-183.   DOI: 10.13371/j.cnki.chin.q.j.m.2023.02.005
    Abstract149)      PDF(pc) (1289KB)(196)       Save
    In this paper, an eco-epidemiological model with time delay is studied. The local stability of the four equilibria, the existence of stability switches about the predation- free equilibrium and the coexistence equilibrium are discussed. It is found that Hopf bifurcations occur when the delay passes through some critical values. Formulae are obtained to determine the direction of bifurcations and the stability of bifurcating periodic solutions by using the normal form theory and center manifold theorem. Some numerical simulations are carried out to illustrate the theoretical results.
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    Virtual Element Method of the Allen-Cahn Equation
    WANG Pei-zhen, TIAN Xu
    Chinese Quarterly Journal of Mathematics    2023, 38 (1): 20-29.   DOI: 10.13371/j.cnki.chin.q.j.m.2023.01.002
    Abstract127)      PDF(pc) (307KB)(184)       Save
     In this article, the virtual element method of the Allen-Cahn equation on a
    polygon grid is discussed in the fully discrete formulation. With the help of the energy
    projection operator, we give the corresponding error estimates in the L2 norm and H1
    norm.
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    Vertex Operators, Littlewood-Richardson Rule for Generalized Symplectic Schur Functions
    HUANG Fang, CHU Yan-jun
    Chinese Quarterly Journal of Mathematics    2022, 37 (3): 301-316.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.03.007
    Abstract130)      PDF(pc) (375KB)(184)       Save
     Littlewood-Richardson rule gives the expansion formula for decomposing a
    product of two Schur functions as a linear sum of Schur functions, while the decomposition
    formula for the multiplication of two symplectic Schur function is also given by the
    combinatorial method. In this paper, we will construct the algebraic forms of the
    decomposition formula for the product of two symplectic Schur functions by using the
    generating functions and vertex operator realizations, and then extend these results to
    generalized symplectic Schur functions.
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    Differential Identities in Prime Rings with Involution
    HUANG Shu-liang
    Chinese Quarterly Journal of Mathematics    2023, 38 (2): 134-144.   DOI: 10.13371/j.cnki.chin.q.j.m.2023.02.003
    Abstract118)      PDF(pc) (319KB)(183)       Save
    Let R be a prime ring of characteristic different from two with the sec- ond involution ∗ and α an automorphism of R . An additive mapping F of R is called a generalized ( α,α )-derivation on R if there exists an ( α,α )-derivation d of R such that F ( xy )= F ( x ) α ( y )+ α ( x ) d ( y ) holds for all x,y∈R. The paper deals with the s- tudy of some commutativity criteria for prime rings with involution. Precisely, we describe the structure of R admitting a generalized ( α,α )-derivation F satisfying any one of the following properties:
    ( i ) F ( xx) −α ( xx) ∈Z ( R ).
    ( ii ) F ( xx )+ α ( xx ) ∈Z ( R ).
    ( iii ) F ( x ) F ( xx) −α ( xx) ∈Z ( R ).
    ( iv ) F ( x ) F (x)+ α ( xx) ∈Z ( R ).
    ( v ) F ( xx) −F ( x ) F (x ) ∈Z ( R ).
    ( vi ) F ( xx) −F (x) F ( x )=0
    for all x∈R . Also, some examples are given to demonstrate that the restriction of the various results is not superfluous. In fact, our results unify and extend several well known theorems in literature.
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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
    Abstract178)      PDF(pc) (279KB)(175)       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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    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
    Abstract141)      PDF(pc) (348KB)(168)       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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    Initial Boundary Value Problem for Pseudo-Parabolic p-Laplacian Type Equation with Logarithmic Nonlinearity
    PAN Jia-hui, FANG Shao-mei
    Chinese Quarterly Journal of Mathematics    2023, 38 (4): 360-369.   DOI: 10.13371/j.cnki.chin.q.j.m.2023.04.003
    Abstract77)      PDF(pc) (358KB)(162)       Save
     In this paper, we study the initial boundary value problem of pseudo-parabolic p-Laplacian type equation, which be use to model some important physical and biological phenomena. By using the potential well method, we obtain the global existence, asymptotic behavior and blow up results of weak solution with subcritical initial energy. Then we also extend these results to the critical initial energy.
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    Existence and Exponential Stability of Almost Periodic Solutions to General BAM Neural Networks with Leakage Delays on Time Scales
    DONG Yan-shou, HAN Yan, DAI Ting-ting
    Chinese Quarterly Journal of Mathematics    2022, 37 (2): 189-202.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.02.008
    Abstract137)      PDF(pc) (885KB)(154)       Save
     In this paper, the existence of almost periodic solutions to general BAM neural
    networks with leakage delays on time scales is first studied, by using the exponential
    dichotomy method of linear differential equations and fixed point theorem. Then, the
    exponential stability of almost periodic solutions to such BAM neural networks on time
    scales is discussed by utilizing differential inequality. Finally, an example is given to
    support our results in this paper and the results are up-to-date.
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    Homology of Bihom-Lie Algebras
    CHENG Yong-sheng, WANG Meng-ping
    Chinese Quarterly Journal of Mathematics    2022, 37 (3): 237-247.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.03.002
    Abstract107)      PDF(pc) (286KB)(151)       Save
     The purpose of this paper is to define Hochschild type homology of Bihom-
    associative algebras and Chevalley-Eilenberg type homology of Bihom-Lie algebras with
    non-trivial coefficients in their bimodules respectively. In particular, we give their low
    order homology in detail.
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    Weighted Analytic Torsion for Weighted Digraphs
    REN Shi-quan, WANG Chong
    Chinese Quarterly Journal of Mathematics    2023, 38 (1): 30-49.   DOI: 10.13371/j.cnki.chin.q.j.m.2023.01.003
    Abstract175)      PDF(pc) (389KB)(139)       Save
     In 2020, Alexander Grigor’yan, Yong Lin and Shing-Tung Yau [6] introduced
    the Reidemeister torsion and the analytic torsion for digraphs by means of the path
    complex and the path homology theory. Based on the analytic torsion for digraphs
    introduced in [6], we consider the notion of weighted analytic torsion for vertex-weighted
    digraphs. For any non-vanishing real functions f and g on the vertex set, we consider the
    vertex-weighted digraphs with the weights ( f,g ). We calculate the ( f,g )-weighted analytic
    torsion by examples and prove that the ( f,g )-weighted analytic torsion only depend on
    the ratio f/g . In particular, if the weight is of the diagonal form ( f,f ), then the weighted
    analytic torsion equals to the usual (un-weighted) torsion.
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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
    Abstract185)      PDF(pc) (344KB)(138)       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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    Independent Roman {2}-Domination in Trees
    LI Bei-bei, SHANG Wei-ping
    Chinese Quarterly Journal of Mathematics    2022, 37 (4): 386-393.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.04.006
    Abstract167)      PDF(pc) (336KB)(137)       Save
    For a graph G = (V,E), a Roman {2}-dominating function f :V → {0,1,2} has the property that for every vertex v ∈V with f(v) = 0, either v is adjacent to at least one vertex u for which f(u) = 2, or at least two vertices uand u2 for which f(u1) =f(u2) = 1. A Roman {2}-dominating function f = (V0,V1,V2) is called independent if V1∪V2 is an independent set. The weight of an independent Roman {2}-dominating function f is the value ω(f) =\sumv∈V f(v), and the independent Roman {2}-domination number i{R2}(G) is the minimum weight of an independent Roman {2}-dominating function on G. In this paper, we characterize all trees with i{R2}(T) =γ(T)+ 1, and give a linear time algorithm to compute the value of i{R2}(T) for any tree T. 
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    Ergodicity of Bandwidth and Cutwidth on Families of Graphs and Trees
    LIN Yi-shu, CHANG Cai-bing, LIU Yan
    Chinese Quarterly Journal of Mathematics    2022, 37 (4): 355-365.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.04.003
    Abstract111)      PDF(pc) (346KB)(136)       Save
    Bandwidth, cutwidth, cyclic bandwidth, bandwidth sum and cyclic bandwidth
    sum are well-known indices about optimal labeling of graphs applied in VLSI design,
    network communications, and other areas involving the graph layout. To design the
    graphs with the given indices, we need to study the ergodicity. Let F be a set of graphs
    under consideration and ϕ an integer-valued function defined on F, namely, ϕ is an index,
    such as bandwidth and cutwidth. If there exists a graph G ∈ F such that ϕ(G) =x for
    any integer x in the interval [a,b], where a and b are the minimum and maximum of ϕ
    on F, respectively, then ϕ is said to have ergodicity on F. Let Gn be the set of simple
    connected graphs with order n and Tn the set of trees with order n. In this paper, we
    investigate the ergodicity of bandwidth, cutwidth, cyclic bandwidth, the bandwidth sum
    and cyclic bandwidth sum on Tn and Gn.

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    A Note on Preemptive Scheduling with Multiple Maintenance Activities to Minimize the Total Late Work
    HE Ru-yan, YUAN Jin-jiang, ZHANG Yuan
    Chinese Quarterly Journal of Mathematics    2022, 37 (4): 331-342.   DOI: 10.13371/j.cnki.chin.q.j.m.2022.04.001
    Abstract119)      PDF(pc) (374KB)(132)       Save
    We study the single-machine preemptive scheduling problem with multiple maintenance activities to minimize the total late work, in which the jobs must be processed in the time space not occupied by the maintenance intervals. For this problem, we present a polynomial algorithm to determine the optimal schedule and establish a formula expression to the optimal value. Moreover, our result is used to correct some minor errors in the literature related to the single-machine (preemptive or non-preemptive) scheduling with one maintenance activity to minimize the total late work. 
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