中国科学院数学与系统科学研究院期刊网

Acta Mathematica Sinica, Chinese Series 2018 Vol.61

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Optimal Decay Estimates of Solutions to the Three-dimensional Generalized MHD Equations
Zhi Jie NAN, Gang WU
Acta Mathematica Sinica, Chinese Series    DOI: 10.12386/A2018sxxb0001
The Number of Zeros of Abelian Integrals for Near-Hamilton System of Degree Three with a Butterfly
Ji Hua YANG, Er Li ZHANG, San Jie LI, Mei LIU
Acta Mathematica Sinica, Chinese Series    DOI: 10.12386/A2018sxxb0002
Modified Maximal Function Theorems in a Nondoubling Quasi-Metric Measure Space and Applications
Hui Ju WANG, Peng Cheng NIU
Acta Mathematica Sinica, Chinese Series    DOI: 10.12386/A2018sxxb0003
Degrees from S3-manifolds to Lens Spaces
Xiao Mo LIU
Acta Mathematica Sinica, Chinese Series    DOI: 10.12386/A2018sxxb0004
The Casimir Number of a Verlinde Modular Category and Its Applications
Zhi Hua WANG, Li Bin LI
Acta Mathematica Sinica, Chinese Series    DOI: 10.12386/A2018sxxb0005
A Linear Recurrence Formula Involving Cubic Gauss Sums and Kloosterman Sums
Li CHEN, Jia Yuan HU
Acta Mathematica Sinica, Chinese Series    DOI: 10.12386/A2018sxxb0006
Hilbert-Schmidt Differences of Composition Operators on Aα2
Li ZHANG, Xiu Jiao CHU
Acta Mathematica Sinica, Chinese Series    DOI: 10.12386/A2018sxxb0007
The Boundedness for an Oscillatory Integral Operator on Multi-dimension with Polynomial Phase
Ming Quan WEI, Dun Yan YAN
Acta Mathematica Sinica, Chinese Series    2018, 61 (1): 89-96.   DOI: 10.12386/A2018sxxb0009
Abstract401)      PDF(pc) (464KB)(329)       Save

We consider the following oscillatory integral operator:

where the function f is assumed to be a Schwartz function on Rn and m, k > 0. In this paper, we characterize the sufficient and necessary conditions which ensure the boundedness for Tm,k,n from Lp(Rn) (1 ≤ p < ∞) to Lq(Rn). In addition, the operator Tm,k,n also maps L1(Rn) into l0(Rn).

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Hochschild Homology and Cyclic Homology of a Self-injective Koszul Algebra
Zhao Hui LI, Yun Ge XU, Ren WANG
Acta Mathematica Sinica, Chinese Series    2018, 61 (1): 97-106.   DOI: 10.12386/A2018sxxb0010
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There is a close connection between Hochschild homology groups of a k-algebra and cycles of the Gabriel quiver associated to the k-algebra. In this paper,based on the minimal projective bimodule resolution of a self-injective Koszul four-point algebra constructed by Furuya, we calculate the dimensions of Hochschild homology spaces of the algebra by using combinatorial methods, and give a k-basis of every Hochschild homology space in terms of cycles. Moreover, we obtain the dimensions of cyclic homology groups of the algebra when the base field k is of zero characteristic.

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Regular Semigroups With Weak Medial Idempotents
Xiang Fei NI, Xiao Jiang GUO
Acta Mathematica Sinica, Chinese Series    2018, 61 (1): 107-122.   DOI: 10.12386/A2018sxxb0011
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In this paper, the concepts of weak medial idempotent and quasi-medial idempotent of regular semigroups are introduced. The aim of this paper is to explore the properties of the two types of idempotents. Several regular semigroups having weak(quasi-) medial idempotents are constructed to indicate the relationship between weak medial idempotents and quasi-medial idempotents, various ways are given to confirm that an idempotent is a weak medial idempotent or a quasi-medial idempotent, and some descriptions of orthodox semigroups in terms of quasi-media idempotents are hold. At last, the structure theorem of every regular semigroup with a quasi-medial idempotent is obtained. As an application of the results, such kind of construction method help us to get a way to determine whether a regular semigroup contains a multiplicative inverse transversal or not.

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The Properties of Closed Theories with Its Application in the Formal Deductive System L*
Hong Bo WU, Ying LIANG
Acta Mathematica Sinica, Chinese Series    2018, 61 (1): 123-134.   DOI: 10.12386/A2018sxxb0012
Abstract565)      PDF(pc) (566KB)(403)       Save

In the Formal Deductive System L* of Fuzzy Propositional Calculus, the notion of closed theory is introduced and its properties are investigated. Furthermore, the completeness of Formal Deductive System L* is proved through closed theory based on formula set F(S). At first, in the formal deductive system L*, a concept of closed theory is introduced, and a method for extending theories to closed theories is given; at second, in the formal deductive system L*, a concept of total closed theory is introduced, and the existence of a total closed theory satisfying relevant conditions is proved; at third, in the formal deductive system L*, the properties of congruence relations determined by closed theories are investigated, a concept of strong congruence relations is introduced to formulas set F(S), and methods of changing each other between strong congruence relations and closed theories are revealed; at fourth, in the formal deductive system L*, it is proved that closed theory style L*-Lindenbaum algebras determined by closed theories are R0-algebras, and a closed theory-L*-Lindenbaum algebra is linear if and only if a closed theory is total; at last, the completeness of the formal deductive system L* is accomplished by making use of total closed theory style L*-Lindenbaum algebras, and the results obtained before have been improved.

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Automorphisms of an Inclusion Ideal Graph over a Total Matrix Ring
Li CHEN
Acta Mathematica Sinica, Chinese Series    2018, 61 (1): 135-142.   DOI: 10.12386/A2018sxxb0013
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The inclusion ideal graph of a ring R, written as ΓI(R), is a directed graph which has all nontrivial left rings of R as vertex set and there is a directed edge from a vertex I1 to a distinct vertex I2 if and only if I1 is properly contained in I2. In addition, the ideal-relation graph of a ring R, written as Γi(R), is also a directed graph which has R as vertex set and there is a directed edge from a vertex A to a distinct vertex B if and only if the left ideal of R generated by A is properly contained in the left ideal generated by B. Let Fq be a finite field, the set of n×n matrices over Fq be denoted by Mn(Fq). In this paper, both the automorphisms of ΓI(Mn(Fq)) and the automorphisms of Γi(Mn(Fq)) are characterized.

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Path Analysis of BMAP and Adjoint MAP of a Q Process
Xiao Yun MO, Xiang Qun YANG
Acta Mathematica Sinica, Chinese Series    2018, 61 (1): 143-154.   DOI: 10.12386/A2018sxxb0014
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This article researches the batch Markov arrival process (BMAP) by using path-analysis method which is different from using conventional matrix analysis method. We are capable of calculating its jumping probability through the representation (Dk, k=0, 1, 2,...) of BMAP, demonstrating the fact that BMAP's phase process is time-homogeneous Markov chain, figuring out the transition probabilities and density matrix of the phase process. Moreover, if we give a Q process J with a finite state space and define the counting process of its jumping points as N, we can demonstrate that adjoint process X*=(N, J) of Q process J is a MAP. The MAP's transition probabilities and representation (D0, D1) are exactly worked out, which are expressed by density matrix Q.

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Dynamical Behavior for a Stochastic Epidemic Model with Nonlinear Incidence
Feng Ying WEI, Qing Teng LIN
Acta Mathematica Sinica, Chinese Series    2018, 61 (1): 155-166.   DOI: 10.12386/A2018sxxb0015
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The extinction and the stationary distribution to a stochastic SEIR epidemic model with nonlinear incidence rate in a population of varying size are discussed. Under moderate conditions, the existence-and-uniqueness of the global solution, exponential stability and the stationary distribution with ergodicity are obtained. By means of linearization and Fourier transform, we prove that the solution obeys a fourdimensional normal distribution, and the mean and the variance matrix are followed. Then numerical simulations are carried out to illustrate our results.

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Large Deviations for a Renewal Randomly Indexed Branching Process
Zhen Long GAO, Liang FANG
Acta Mathematica Sinica, Chinese Series    2018, 61 (1): 167-176.   DOI: 10.12386/A2018sxxb0016
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We consider a branching process indexed by a general renewal process. Assume that the renewal distribution satisfies the Cramér condition and the branching process belongs to the Böttcher case, i.e., if always at least two offspring are born, we obtain the large deviations of such process.

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Survey on Kadison-Singer Algebras
Ai Ju DONG, Guang Feng CHEN, Wei Qing YANG, Yun Liang ZHANG, Jun Long AN
Acta Mathematica Sinica, Chinese Series    2018, 61 (2): 177-196.   DOI: 10.12386/A2018sxxb0017
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The background for the introduction of Kadison-Singer algebras (KSalgebras, for short) is reviewed. Definitions and basics properties are explained. Studies on hyperfinite KS-algebras, non-hyperfinite case, KS-lattices and strong KS-algebras are described in details, as well as their connections with classical open problems such as the invariant subspace problem, Kadison's transitive algebra problem, von Neumann algebra generator problem. Operations on non-selfadjoint operator algebras are also discussed and two new operations are included in the discussion. Sixteen open problems are listed with some explanations in the end.

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Ground State Solutions for Some Kirchhoff Type Problems with Critical Growth in R3
Lie Jun SHEN
Acta Mathematica Sinica, Chinese Series    2018, 61 (2): 197-216.   DOI: 10.12386/A2018sxxb0018
Abstract474)      PDF(pc) (656KB)(403)       Save

We are concerned with a class of Kirchhoff problem

where a, b > 0 are constants. The existence of ground state solutions, i.e., nontrivial solutions with least possible energy of this Kirchhoff problem is obtained. Moreover, when Q ≡ 1, under suitable conditions on h(x), we prove the existence of ground state solutions for the the following Kirchhoff problem
.

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Symplectic Neighborhood Theorem for Symplectic Orbifold Groupoids
Cheng Yong DU, Bo Hui CHEN, Rui WANG
Acta Mathematica Sinica, Chinese Series    2018, 61 (2): 217-232.   DOI: 10.12386/A2018sxxb0019
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We give a geometric definition of sub-orbifold groupoid, and a criterion for determining a sub-orbifold groupoid. Then we prove the existence of orbifold tubular neighborhoods of compact sub-orbifold groupoids, the existence of symplectic neighborhoods of compact symplectic sub-orbifold groupoids in symplectic orbifold groupoids, and, the existence of Lagrangian neighborhoods of compact Lagrangian sub-orbifold groupoids.

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Positive Solutions for a Nonlocal Critical Problem with Singular Weight in Dimension Four
Jia Feng LIAO, Hong Ying LI, Peng ZHANG
Acta Mathematica Sinica, Chinese Series    2018, 61 (2): 233-242.   DOI: 10.12386/A2018sxxb0020
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We are interested in considering the following nonlocal critical problem

where Ω ⊂ R4 is a smooth bounded domain with 0 ∈ Ω, a ≥ 0, b, λ, μ > 0, 1 < q < 2, 0 < β < 2. By using the variational method, some existence and multiplicity results are obtained.

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Height and Topological Conjugacy of Piecewise Monotonic Functions
Ping Ping ZHANG, Wei Nian LI
Acta Mathematica Sinica, Chinese Series    2018, 61 (2): 243-260.   DOI: 10.12386/A2018sxxb0021
Abstract516)      PDF(pc) (651KB)(348)       Save

Computing height of piecewise monotonic functions is difficult because the value of functions may interact each other under iteration. In this paper we consider the set of continuous functions with a single non-monotonic point. We first present a sufficient and necessary condition for heights which gives a classification of those functions. Then we provide an equivalent condition and a new construction method for topological conjugacy for a nonempty subset of the mentioned continuous functions. Furthermore, we prove that topological conjugacy is a sufficient but not necessary condition for equal heights of piecewise monotonic functions. Finally, some examples are given to illustrate our results.

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Convergence for Random Variables with General Moment Conditions
De Hua QIU, Ping Yan CHEN, Zheng Hua DUAN
Acta Mathematica Sinica, Chinese Series    2018, 61 (2): 261-272.   DOI: 10.12386/A2018sxxb0022
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Convergence for identically distributed negatively associated (NA) random variables and independent and identically distributed (i.i.d.) random variables are studied under general moment conditions, the extension of the Baum-Katz Theorem and strong law of large numbers are obtained. The theorems extend the related known works in the literature.

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The Lp-Dual Mixed Geominimal Surface Areas of Multiple Star Bodies and Related Inequalities
Li YAN Wei, Dong WANG
Acta Mathematica Sinica, Chinese Series    2018, 61 (2): 273-288.   DOI: 10.12386/A2018sxxb0023
Abstract394)      PDF(pc) (510KB)(346)       Save

Ye etc introduced the Lp-mixed geominimal surface areas of multiple convex bodies for any real p(p≠-n). In this paper, we define the Lp-dual mixed geominimal surface areas of multiple star bodies for any real p(pn), and establish some inequalities related to this concept.

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Nonuniform Average Sampling of Shift-invariant Signals with Generators in a Hybrid-norm Space
Xiao FAN, Ying Chun JIANG
Acta Mathematica Sinica, Chinese Series    2018, 61 (2): 289-300.   DOI: 10.12386/A2018sxxb0024
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Sampling in shift-invariant subspaces of Lp is commonly studied under the requirement that the generator is in a Wiener amalgam space independent of p, but such condition is too strong because it does not allow us to control p. In this paper, we mainly discuss the nonuniform average sampling and reconstruction of signals in a non-decaying shift-invariant space under the assumption that the generator is in a hybrid-norm space. The new condition is weaker than the Wiener amalgam space and depends on the parameter p. Based on some lemmas in hybrid-norm spaces, we first give the sampling stability for two kinds of average sampling functionals, and then the corresponding iterative reconstruction algorithms with exponential convergence are established.

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Canonical Forms of Coupled Self-adjoint Boundary Conditions for Regular Differential Operators of Order Four
Lan QING, Xiao Ling HAO, Jiong SUN
Acta Mathematica Sinica, Chinese Series    2018, 61 (2): 301-308.   DOI: 10.12386/A2018sxxb0025
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We present the canonical forms of coupled self-adjoint boundary conditions for regular differential operators of order four by using new methods. In this new canonical forms, the four small block matrices are symmetric, and the determinant has absolute value equal to 1. This fourth order form is quite similar to the new second order one, and it provides a new way to give the canonical forms of the self-adjoint boundary condition for general high-order differential operators.

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Endpoint Estimates of a Class of Singular Integral Operators with Rough Kernels
Qiang HUANG, Zheng WANG
Acta Mathematica Sinica, Chinese Series    2018, 61 (2): 309-316.   DOI: 10.12386/A2018sxxb0026
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Assume TΩ is the Calderón-Zygmund singular integral operator with rough kernel and I is the closed arc of unit circle that I ? S1. In this paper, we prove that if Ω is supported in I and monotonous on I, then TΩ is bounded from Hardy space H1(R2) to L1(R2) if and only if||Ω||L log L < ∞.

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Limit Theorems for Controlled Branching Processes in Random Environments
Ying Qiu LI, De Ru LI, Sheng PAN, Xue Lian PENG
Acta Mathematica Sinica, Chinese Series    2018, 61 (2): 317-326.   DOI: 10.12386/A2018sxxb0027
Abstract388)      PDF(pc) (466KB)(352)       Save

The limiting behaviors for controlled branching processes in random environments are discussed. Under the normalization factor {Sn:n ∈ N}, the normalization processes {?n:n ∈ N} of are studied, and the sufficient conditions of {?n:n ∈ N} a.s., L1 and L2 convergence are given; A sufficient condition and a necessary condition for convergence to a non-degenerate at 0 random variable are got; Under the normalization factor {In:n ∈ N}, the normalization processes {Wn:n ∈ N} are discussed, and the sufficient conditions of {Wn:n ∈ N} a.s., and L1 convergence are obtained.

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On the Integration by Parts Formula and Martingale Representation of Fractional Diffusion Measure
Xiao Xia SUN
Acta Mathematica Sinica, Chinese Series    2018, 61 (2): 327-336.   DOI: 10.12386/A2018sxxb0028
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We study the stochastic analysis of the measure determined by fractional diffusion process (fractional diffusion measure). We first give the pull back formula by Bismut method, then establish the integration by parts formula for fractional diffusion measure. Finally, we generalize the classic Clark-Ocone theorem to martingale representation theorem under fractional diffusion measure.

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The Fundamental Coupling Theorem for Inhomogeneous Markov Processes
Juan SONG, Ming ZHANG
Acta Mathematica Sinica, Chinese Series    2018, 61 (2): 337-346.   DOI: 10.12386/A2018sxxb0029
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We apply the coupling method in inhomogeneous Markov processes, and generalize the fundamental coupling theorem of homogeneous Markov processes, which provides a theoretical basis for the further study of the coupling methord for inhomogeneous Markov processes.

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The Abscissa of Convergence on the Dirichlet Series Σn=0aneλns
Yin Ying KONG, Xi LUO
Acta Mathematica Sinica, Chinese Series    2018, 61 (2): 347-352.   DOI: 10.12386/A2018sxxb0030
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We define the abscissa of convergence σc, the uniform abscissa of convergence σu and the absolute abscissa of convergence σa on Dirichlet series Σn=0 aneλns,use the relationship between the index λn and the coefficients an to estimate the three convergence abscissas, and obtain that the convergence conditions of two Dirichlet series Σn=0 aneλns and Σn=0 anens are the same.

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An Additive-Multiplicative Subdistribution Hazard Model with Covariates-Dependent Weight for Competing Risks Data
Wan Xing LI, Yong Hong LONG, Qing Shui XUE
Acta Mathematica Sinica, Chinese Series    2018, 61 (3): 353-374.   DOI: 10.12386/A2018sxxb0031
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We propose a flexible additive-multiplicative hazard model allowing the additive time-varying effects of covariate for the subdistribution in a competing risks circumstance. For inference on the model parameters, weighted estimating equation approaches under an covariates-dependent adjusted weight by fitting the Cox proportional hazard model for the censoring distribution are established. In addition, large number properties and a goodness-of-fit test procedure are presented. The finite sample behavior of the proposed estimators is evaluated through simulation studies, estimators from the proposed method perform satisfactorily on reduction of the bias, and an application to a competing risks data set from a follicular cell lymphoma study is illustrated.

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Instability for the Standing Wave of Generalized Davey-Stewartson Equation
Xiao Guang LI, Jian ZHANG, Zhong Tao YUE
Acta Mathematica Sinica, Chinese Series    2018, 61 (3): 375-382.   DOI: 10.12386/A2018sxxb0032
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The aim of this paper is to study the standing wave of the generalized Davey-Stewartson equation iutu+a|u|p-1u+E1(|u|2)u=0, t ≥ 0,x∈Rn, where a,b > 0, 1 < p < (n-2)/((n+2)+), n∈{2,3}. When 1+4/np < (n-2)/((n+2)+),[Sharp threshold of global existence and instability of standing wave for a Davey-Stewartson system, Commun. Math. Phys., 2008, 283:93-125], under an assumption about the frequency of the standing wave, obtained the strongly instability of the ground state standing waves. In the present paper, We establish the same conclusion without that assumption.

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Large Deviation Principle for Homeomorphism Flows of Stochastic Hamiltonian Systems
Jie REN
Acta Mathematica Sinica, Chinese Series    2018, 61 (3): 383-402.   DOI: 10.12386/A2018sxxb0033
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We prove a large deviation principle for homeomorphism flows of stochastic differential equations (SDEs) without global Lipschitz conditions and apply it to stochastic Hamiltonian systems, which in particular covers the following nonlinear oscillator equation:
?t=C0?t-Zt3+Θ(Zt)?t,(Z0,?0)=(z,u)∈R2,
where C0∈R, Θ∈C2(R) has a bounded first order derivative, and ?t is a onedimensional Brownian white noise.

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Precise Asymptotics in the Law of Iterated Logarithm for the Moment Convergence of NA Random Variables
Ya Yun ZHANG, Qun Ying WU
Acta Mathematica Sinica, Chinese Series    2018, 61 (3): 403-410.   DOI: 10.12386/A2018sxxb0034
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Let {Xn,n ≥ 1} be a sequence of strictly stationary NA random variables and set Sn=∑i=1nXi,Mn=max1 ≤ i ≤ n|Si|. Under some proper conditions, the precise asymptotics in the law of iterated logarithm for the moment convergence of NA random variables of the partial sum and the maximum of the partial sum are obtained.

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Positive Solution for a Class of Elliptic Equations Involving Nonlocal Term and Critical Term
Jiu LIU, Jia Feng LIAO, Chun Lei TANG
Acta Mathematica Sinica, Chinese Series    2018, 61 (3): 411-430.   DOI: 10.12386/A2018sxxb0035
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In the paper, the following Kirchhoff-type equations with critical exponent (a+bR3[|∇u|2+V(x)u2]dx)·[-△u+V(x)u]=μf(x,u)+K(x)u5,x∈R3, is studied, in which a, b, μ > 0, the potential functions V, K satisfy some conditions and the nonlinear term f verifies sup-cubic or sup-linear growth. With the aid of the mountain pass theorem, three existence results are obtained.

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Equivalent Properties of CD Inequalities on Graphs
Yong LIN, Shuang LIU
Acta Mathematica Sinica, Chinese Series    2018, 61 (3): 431-440.   DOI: 10.12386/A2018sxxb0036
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We study some equivalent properties of the curvature dimension inequality CD(n,K) on locally finite graphs. These equivalences are gradient estimate, Poincaré type inequalities and reverse Poincaré inequalities. We also obtain one equivalent property of gradient estimate for a new notion of curvature dimension inequality CDE (∞,K) at the same assumption on graphs.

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A Note on Zassenhaus's Conjecture
Jin Ke HAI, Ji Dong GUO
Acta Mathematica Sinica, Chinese Series    2018, 61 (3): 441-446.   DOI: 10.12386/A2018sxxb0037
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In this note, we investigate the partial augmentations of the normalized torsion units in integral group rings of the direct product of two finite groups. It is proved that every normalized torsion unit is conjugate to one element in the group within the rational group algebra under some conditions.

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On the Closed Range of Block Operator Matrices
Suriguga, De Yu WU, Alatancang
Acta Mathematica Sinica, Chinese Series    2018, 61 (3): 447-456.   DOI: 10.12386/A2018sxxb0038
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In this paper, the closed range of block operator matrices is studied. Using the perturbation theory and Hyers-Ulam stability, the sufficient conditions of the closed range of operator matrix are given. In the end, some examples are given to illustrate the effectiveness of the proposed criterion.

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The Limit Theory of One Kind of Multi-branching Process in Random Environment
Wei Gang WANG, Zhen Long GAO
Acta Mathematica Sinica, Chinese Series    2018, 61 (3): 457-468.   DOI: 10.12386/A2018sxxb0039
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We defined a multi-branching process in varying environment by it's fitness. We studied the properties of its generating function and gave the recurrence relation of the generating function. We calculated the expectation and variance of the process, just like Galton-Watson process, we studied its extinction probability and constructed a nonnegative martingale, in the case that the first and second order moments of offspring are bounded, we also proved that this martingale converged in L2.

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Stochastic Volatility and the q Theory of Investment
Wen Li HUANG
Acta Mathematica Sinica, Chinese Series    2018, 61 (3): 469-476.   DOI: 10.12386/A2018sxxb0040
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We introduce stochastic volatility to Tobin's q theory, in order to find how volatility of productivity shock affects a firm's value and its investment decision. We show that volatility of productivity shock has significant effect on firm's Tobin's q, which decreases as volatility rises and the effect gets more obvious as volatility gets bigger. On the other hand, this effect can also affect firm's investment decision because the decrease of Tobin's q can reduce firm's investment, and the effect gets larger when volatility rises too. We also illustrate the effect of volatility upon firm's assets in place and growth opportunities. Our assumption that volatility of productivity shock is stochastic is more realistic than existing literature, so our conclusion is able to provide a reference for firm's valuation and investment decision.

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