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STARLIKENESS ASSOCIATED WITH THE SINE HYPERBOLIC FUNCTION

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Acta Mathematica Scientia 2024年第4期44卷 1244-1270页

作者： Mohsan RAZA Hadiqa ZAHID Jinlin LIU department of {1. Government College University FaisalabadFaisalabad 38000Pakistan department of Information Science Yangzhou UniversityYangzhou 225002China

Let q_(λ)(z)=1.λsinh(ζ),0<λ<1.sinh(1.be a non-vanishing analytic function in the open unit *** introduce a subclass S^(*)(q_(λ))of starlike functions which contains the functions f such that zf'/f is subordinated... 详细信息

Let q_(λ)(z)=1.λsinh(ζ),01.sinh(1.be a non-vanishing analytic function in the open unit *** introduce a subclass S^(*)(q_(λ))of starlike functions which contains the functions f such that zf'/f is subordinated by q_(λ).We establish inclusion and radii results for the class S^(*)(q_(λ))for several known classes of starlike ***,we obtain sharp coefficient bounds and sharp Hankel determinants of order two for the class S^(*)(q_(λ)).We also find a sharp bound for the third Hankel determinant for the caseλ=1.2.

关键词： starlike functions sine hyperbolic functions radii problems coefficient bounds Hankel determinants

Discrete Boltzmann model with split collision for nonequilibrium reactive flows

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Communications in Theoretical Physics 2024年第8期76卷 166-188页

作者： Chuandong Lin Kai H Luo Huilin Lai Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen University Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power Engineering Tsinghua University department of Mechanical Engineering National University of Singapore department of Mechanical Engineering University College London School of mathematics and Statistics Key Laboratory of Analytical Mathematics and Applications (Ministry of Education) Fujian Key Laboratory of Analytical Mathematics and Applications (FJKLAMA) Center for Applied Mathematics of Fujian Province (FJNU) Fujian Normal University

A multi-relaxation-time discrete Boltzmann model(DBM) with split collision is proposed for both subsonic and supersonic compressible reacting flows, where chemical reactions take place among various components. The physical model is based on a unified set of discrete Boltzmann equations that describes the evolution of each chemical species with adjustable acceleration, specific heat ratio, and Prandtl number. On the right-hand side of discrete Boltzmann equations, the collision,force, and reaction terms denote the change rates of distribution functions due to self-and crosscollisions, external forces, and chemical reactions, respectively. The source terms can be calculated in three ways, among which the matrix inversion method possesses the highest physical accuracy and computational efficiency. Through Chapman–Enskog analysis, it is proved that the DBM is consistent with the reactive Navier–Stokes equations, Fick's law and the Stefan–Maxwell diffusion equation in the hydrodynamic limit. Compared with the one-step-relaxation model, the split collision model offers a detailed and precise description of hydrodynamic, thermodynamic, and chemical nonequilibrium effects. Finally, the model is validated by six benchmarks, including multicomponent diffusion, mixture in the force field, Kelvin–Helmholtz instability, flame at constant pressure, opposing chemical reaction, and steady detonation.

关键词： detonation discrete Boltzmann method nonequilibrium effect reactive flow

Dynamical behaviors of a constant prey refuge ratio-dependent prey-predator model with Allee and fear effects

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International Journal of Biomathematics 2024年第1期17卷 227-250页

作者： Soumitra Pal Pijush Panday Nikhil Pal A.K.Misra Joydev Chattopadhyays department of {1. Institute of Science Banaras Hindu University Varanasi 221005India department of Mathematical and Statistical Sciences University of Alberta EdmontonAB T6G 2G1Canada department of {1. Visva-Bharati Santiniketan 731235India Agricultural and Ecological Research Unit Indian Statistical Institute 203 B.T.RoadKolkata 700108India

In this paper,we consider a nonlinear ratio-dependent prey-predator model with constant prey refuge in the prey *** Allee and fear phenomena are incorporated explicitly in the growth rate of the prey *** qualitative behaviors of the proposed model are investigated around the equilibrium points in *** bifurcation including its direction and stability for the model is also *** observe that fear of predation risk can have both stabilizing and destabilizing effects and induces bubbling phenomenon in the *** is also observed that for a fixed strength of fear,an increase in the Allee parameter makes the system unstable,whereas an increase in prey refuge drives the system toward ***,higher values of both the Allee and prey refuge parameters have negative impacts and the populations go to ***,we explore the variation of densities of the populations in different bi-parameter spaces,where the coexistence equilibrium point remains *** simulations are carried out to explore the dynamical behaviors of the system with the help of MATLAB software.

关键词： Predator-prey system Allee effect fear effect prey refuge bifurcation population density

Nonlinear Extrapolation Estimates of π

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 91-108页

作者： Wen-qing Xu Sha-sha Wang Da-chuan Xu Beijing Institute for Scientific and Engineering Computing Beijing University of TechnologyBeijing100124China department of {1. and Statistics California State UniversityLong BeachCalifornia90840USA department of {1. and Physics Shijiazhuang Tiedao UniversityShijiazhuang050043China

The classical Archimedean approximation of π uses the semiperimeter or area of regular polygons inscribed in or circumscribed about a unit circle in R~2 and it is well-known that by using linear combinations of these basic estimates,modern extrapolation techniques can greatly speed up the approximation ***,when n vertices are randomly selected on the circle,the semiperimeter and area of the corresponding random inscribed and circumscribing polygons are known to converge to π almost surely as n→∞,and by further applying extrapolation processes,faster convergence rates can also be achieved through similar linear combinations of the semiperimeter and area of these random *** this paper,we further develop nonlinear extrapolation methods for approximating π through certain nonlinear functions of the semiperimeter and area of such *** focus on two types of extrapolation estimates of the forms χ_n=S_n~αA_n~β and Y_n(p)=(αS_n~p+βA_n~p)~(1.p) where α+β=1.p≠0,and Sn and An respectively represents the semiperimeter and area of a random n-gon inscribed in the unit circle in R~2,and Xn may be viewed as the limit of Y_n(p) when p→*** deriving probabilistic asymptotic expansions with carefully controlled error estimates for Xn and Y_n(p),we show that the choice α=4/3,β=-1.3 minimizes the approximation error in both cases,and their distributions are also asymptotically normal.

关键词： Archimedean polygons random polygons approximations ofπ extrapolation processes asymptotic convergence

Special Unipotent Representations of Simple Linear Lie Groups of Type A

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Acta Mathematica Sinica,English Series 2024年第3期40卷 707-716页

作者： Dan BARBASCH Jia Jun MA Bin Yong SUN Chen Bo ZHU department of {1. Cornell UniversityIthacaNY 14853USA School of Mathematical Sciences Xiamen UniversityXiamen 361005P.R.China department of {1. Xiamen University Malaysia CampusSepangSelangor Darul Ehsan43900Malaysia Institute for Advanced Study in mathematics&New Cornerstone Science Laboratory Zhejiang UniversityHangzhou 310058P.R.China department of {1. National University of Singapore10 Lower Kent Ridge RoadSingapore 119076

Let G be a special linear group over the real,the complex or the quaternion,or a special unitary *** this note,we determine all special unipotent representations of G in the sense of Arthur and Barbasch-Vogan,and show... 详细信息

关键词： Special unipotent representations unitary representations coherent continuation Weyl group representations

Proximal Linearized Minimization Algorithm for Nonsmooth Nonconvex Minimization Problems in Image Deblurring with Impulse Noise

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Journal of Mathematical Research with Applications 2024年第1期44卷 122-142页

作者： Shirong DENG Yuchao TANG School of mathematics and Information Science Guangzhou University department of {1. Nanchang University

Impulse noise removal is an important task in image restoration. In this paper, we introduce a general nonsmooth nonconvex model for recovering images degraded by blur and impulsive noise, which can easily include some prior information, such as box constraint or low rank, etc. To deal with the nonconvex problem, we employ the proximal linearized minimization algorithm. For the subproblem, we use the alternating direction method of multipliers to solve it. Furthermore, based on the assumption that the objective function satisfies the KurdykaLojasiewicz property, we prove the global convergence of the proposed algorithm. Numerical experiments demonstrate that our method outperforms both the l1.V and Nonconvex TV models in terms of subjective and objective quality measurements.

关键词： nonconvex data fidelity term impulse noise total variation proximal linearized minimization

Dynamical complexity of Anosov systems driven by a quasi-periodic force

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Science China mathematics 2024年

作者： Wen Huang Zeng Lian Kening Lu department of {1. University of Science and Technology of China School of mathematics Sichuan University

Consider C2Anosov systems on a compact manifold driven by a quasi-periodic force. We study their dynamical complexity on various levels from the perspectives of both path-wise dynamics and stochastic processes. Assuming that these systems are non-wandering（i.e., every point in the phase space is nonwandering）, we prove a set of results:（1. the existence of abundance of random periodic points;（2） a random Livsic theorem;（3） a random Ma?n′e-Bousch-Conze-Guivarc'h lemma;（4） the existence of strong random horseshoes. Additionally, a concrete example constructed on a 2-dimensional torus is also given to uncover some interesting phenomena of the systems.

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Anisotropic quintessence compact star in f(T)gravity with Tolman–Kuchowicz metric potentials

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Communications in Theoretical Physics 2024年第1期76卷 61-75页

作者： Piyali Bhar Farook Rahaman Shyam Das Somi Aktar Abdelghani Errehymy department of {1. Government General Degree College SingurHooghlyWest Bengal 712409India department of {1. Jadavpur UniversityKolkata 700032West BengalIndia department of Physics Malda College MaldaWest Bengal 732101India Astrophysics Research Centre School of MathematicsStatistics and Computer ScienceUniversity of KwaZulu-NatalPrivate Bag X54001Durban 4000South Africa

To obtain analytically relativistic quintessence anisotropic spherical solutions in the f(T)paradigm is the primary objective of this *** do this,the pressure anisotropy condition is imposed,and we employ a metric potential of the Tolman–Kuchowicz(TK)*** also suppose that our current model incorporates a quintessence field characterized by a parameterωq,in addition to the anisotropic matter *** the presence of the parameterα,the field equations are modified by the choice of the f(T)*** f(T)gravity parameterαadds new components to the basic physical characteristics,such as density,pressure,subliminal sound velocity,surface redshift,etc,of the present *** selecting the compact star Her X-1.and varyingαfrom 0.5 to 2.5,we examined all the physical characteristics of the model parameter of the *** graphical process demonstrates that a more compact item is produced with greater values ofα.The hydrostatic equilibrium condition of the model is discussed,as well as the mass-radius relationship for our current model is obtained.

关键词： quintessence star f(T)gravity stability condition

DYNAMICS FOR A CHEMOTAXIS MODEL WITH GENERAL LOGISTIC DAMPING AND SIGNAL DEPENDENT MOTILITY

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Acta Mathematica Scientia 2024年第3期44卷 1046-1063页

作者：涂馨予穆春来邱蜀燕张静 School of mathematics and Statistics Southwest UniversityChongqing400715China department of Applied {1. The Hong Kong Polytechnic UniversityHung HomHong KongChina College of mathematics and Statistics Chongqing UniversityChongqing401331China School of Sciences Southwest Petroleum UniversityChengdu610500China

In this paper,we consider the fully parabolic Chemotaxis system with the general logistic source{ut=Δ(γ(v)u)+λu-μu^(k),x∈Ω,t>0,vt=△v+wz,x∈Ω,t>0,wt=-wz,x∈Ω,t>0,zt=△z-z+u,x∈Ω,t>0 whereΩ⊂ℝn(n≥1.is a smooth and bounded domain,λ≥0,μ≥0,κ>1.and the motility function satisfies thatγ(v)∈C3([0,∞)),γ(v)>0,γ′(v)≤0 for all v≥*** the Neumann boundary condition,we obtain the global boundedness of solutions if one of the following conditions holds:(i)λ=μ=0,1.nλ3;(ii)λ>0,μ>0,combined withκ>1.1.n≤3 or k>n+2/4,,n>***,we prove that the solution (u, v, w, z) exponentially converges to the constant steady state ((λ/μ)1.k-1.∫Ωv0dx+∫Ωw0dx/|Ω|,0,(λ/μ)1.k-1..

关键词： chemotaxis signal-dependent motility logistic source boundedness asymptotic behavior