Table of Content

25 October 2008, Volume 28 Issue 5 Previous Issue    Next Issue

For Selected:

View Abstracts

Download Citations EndNote Reference Manager ProCite BibTeX RefWorks

Toggle Thumbnails

Articles

Select

L2 Concentration Phenomenon of Nonlinear Schrödinger vskip Equation with a Harmonic Potential Zhong Sijia; Fang Daoyuan Acta mathematica scientia,Series A. 2008, 28 (5):  785-793.  Abstract ( 1790 )   RICH HTML PDF (317KB) ( 1200 )   Save In this paper, the authors consider the L2 concentration phenomenon of nonlinear Schrödinger equation with a harmonic potential in L2-critical case. At the same time the authors also estimate the blow up points and give a condition of global well posedness. Related Articles | Metrics

Select

R&D Competition Project Strategic Investment in Asymmetrical Case Xue Minggao; Gong Pu Acta mathematica scientia,Series A. 2008, 28 (5):  794-801.  Abstract ( 1741 )   RICH HTML PDF (385KB) ( 1254 )   Save In asymmetrical case, the paper considers irreversible strategic investment in competing research and development (R&D) projects with technological uncertainty and uncertainty of future returns. Using real option game theory and stochastic optimal control approach, this paper presents the optimal investment threshold values and the optimal investment rule of hight-efficient firm (leader), and showed that the investment threshold values are reduced by competition of two firms. The mixed investment strategy for two firms is discussed and gives the probability for each firm exercise the option to invest, also presents the probability of simultaneous exercise of the option to invest for two firms in the paper. Finally, it uses an example from innovation case to show that this paper’s results are reasonable. Related Articles | Metrics

Select

A Note on Unicity of Meromorphic Functions Lei Chunlin; Fang Mingliang; Yang Degui; Wang Xueqin Acta mathematica scientia,Series A. 2008, 28 (5):  802-807.  Abstract ( 1806 )   RICH HTML PDF (221KB) ( 1349 )   Save Let f be a nonconstant meromorphic function, n(≥ 4) be a positive integer,and a be a nonzero finite complex number. If f n and (f n)’ share a CM, then f=ce z/n, where c is a nonzero constant. Related Articles | Metrics

Select

Comparing Identifiability Criteria for Causal Effects in Gaussian Causal Models Zhao Hui; Zheng Zhongguo Acta mathematica scientia,Series A. 2008, 28 (5):  808-817.  Abstract ( 1840 )   RICH HTML PDF (421KB) ( 1255 )   Save In a Gaussian causal model, there may exist several criteria for the identification of the same causal effect, but the corresponding estimators may be different from each other. This paper consideres three popular identifiability criteria, front-door, back-door and instrumental variables criteria for causal effects, compares their estimate efficiencies and gives some simulations. These results can offer guidances for choosing better identifiability criterion in practice. Related Articles | Metrics

Select

A Class of Shock Solution for Quasilinear Robin Problems Mo Jiaqi Acta mathematica scientia,Series A. 2008, 28 (5):  818-822.  Abstract ( 1830 )   RICH HTML PDF (261KB) ( 1376 )   Save A class of Robin two points boundary value problems are considered. Under suitable conditions, using the transformation of stretched variable, shock layer corrective term near the interior point in the interval is constructed. And using the theory of differential inequalities the existence, uniform validity and asymptotic behavior of solution for the original boundary value problem are proved. Related Articles | Metrics

Select

Reverse Poincaré Inequalities of the Minimizers for the Heisenberg Group Target Jia Gao Acta mathematica scientia,Series A. 2008, 28 (5):  823-830.  Abstract ( 1492 )   RICH HTML PDF (281KB) ( 1205 )   Save In this paper some reverse Poincaré type inequalities are obtained for the minimizers of the Heisenberg group target. Related Articles | Metrics

Select

Existence Theorem of Micro-Tangent Sets of Continuous Functions Zhao Peibiao; Yang Xiaoping Acta mathematica scientia,Series A. 2008, 28 (5):  831-839.  Abstract ( 1543 )   RICH HTML PDF (369KB) ( 1454 )   Save We prove the existence theorem: there are many Micro-tangent sets of each function of some residual set of c [0,1] in the sense of Hausdorff metric and that of distribution, respectively. In other words, the typical continuous function has a rich (universal) micro-tangent set structure at many points. This generalizes the results offered by Z.Buczolich [1]. Related Articles | Metrics

Select

On the Global Convergence of the Hager-Zhang Conjugate Gradient Method with Armijo Line Search Zhang Li; Zhou Weijun Acta mathematica scientia,Series A. 2008, 28 (5):  840-845.  Abstract ( 1869 )   RICH HTML PDF (267KB) ( 1235 )   Save Hager and Zhang in [4] proposed a new nonlinear conjugate gradient method (HZ method) and proved that this method is globally convergent when the line search fulfills the Wolfe conditions or the Goldstein’s conditions for strongly convex functions. But no global convergence results were obtained for nonconvex objective functions with Armijo line search. In this paper, the authors introduce a cautious HZ method and prove that the proposed method with Armijo line search converges globally even if the minimization function is nonconvex. The authors also present some numerical results to show the efficiency of the proposed method. Related Articles | Metrics

Select

The Boundary Value Problem with Haseman Shift for Regular Functions on Unbounded Domains in Clifford Analysis Xu Na; Qiao Yuying Acta mathematica scientia,Series A. 2008, 28 (5):  846-855.  Abstract ( 1987 )   RICH HTML PDF (334KB) ( 1283 )   Save On the basis of the introduction of the modified Cauchy kernel, this paper deals with the boundary value problem with Haseman shift for regular functions on unbounded domains: a(t)Φ+(t)+b(t)Φ-(d(t))+c(t)Φ-(t)=g(t). Firstly, the authors give the Plemelj formula functions on unbounded domains. Then, by the integral equation method and the fixed-point theorem, the authors prove the existence and uniqueness of the solution for the problem. Related Articles | Metrics

Select

Algebroid Solutions of Higher-Order Partial Differential Equations on Cm Gao Lingyun Acta mathematica scientia,Series A. 2008, 28 (5):  856-862.  Abstract ( 1749 )   RICH HTML PDF (266KB) ( 1145 )   Save In this paper the author investigates the problem of existence of algebroid solutions of higher-order partial differential equations in several complex variables by using value distribution theory and techniques in several complex variables.A Malmquist type theorem for higher-order partial differential equations on Cm is established. Related Articles | Metrics

Select

Random Non-autonomous Logistic Models Li Junping; Li Min Acta mathematica scientia,Series A. 2008, 28 (5):  863-869.  Abstract ( 1625 )   RICH HTML PDF (330KB) ( 1423 )   Save This paper is devoted to studying the non-autonomous Logistic model: X’(t)=rX(t)(1-X(t)/K(t) (K(t)>0) with random disturbance by using the theory of Markov skeleton processes, and its one-dimensional distribution and condition for stability are presented. Related Articles | Metrics

Select

Stability and Boundedness of Solutions and Existence of Almost Periodic Solution for Difference Equations Yang Xitao Acta mathematica scientia,Series A. 2008, 28 (5):  870-878.  Abstract ( 2157 )   RICH HTML PDF (273KB) ( 1202 )   Save By using Liapunov function, the author establishes sufficient and necessary conditions for the uniform stability, uniformly asymptotic stability and exponential stability of solutions for a high dimension difference equation. Moreover, the author also proves that the uniformly asymptotic stability implies the boundedness of solutions. A sufficient condition is given for the existence and uniformly asymptotic stability of almost periodic solutions for almost periodic difference equations. Related Articles | Metrics

Select

On a New Singular Direction of Algebroidal Function Wu Zhaojun; Sun Daochun Acta mathematica scientia,Series A. 2008, 28 (5):  879-885.  Abstract ( 1649 )   RICH HTML PDF (297KB) ( 1135 )   Save In this paper, by using spherical characteristic function T(r, w), the authors define and establish the existence of a new singular direction for the algebroidal function w, namely a T direction, for which the characteristic function T(r, w) is used as a comparison function. Moreover, the authors prove that the number of exceptional values is at most 2+[δx] ≤ 2 ν. Related Articles | Metrics

Select

The Fourier Pseudo-spectral Approximation of the Large-time Problem of Kolmogorov-Spieqel-Siveshinky Equation Liang Zongqi Acta mathematica scientia,Series A. 2008, 28 (5):  886-896.  Abstract ( 1764 )   RICH HTML PDF (683KB) ( 1168 )   Save The paper is concerned with the Kolmogorov-Spieqel-Siveshinky equation with periodic initial value problems. The long-time behavior of the solutions for semi-discrete Fourier pseudo-spectral scheme is studied.The convergence and the existence of the global attractors for the discrete system is proposed. The full-discrete Fourier pseudo-spectral explicit scheme and its convergence is discussed. Finally, the credibility of the scheme is examined by numerical examples to show that the scheme is stable for a long time and the step-length is long. The orbits in the phase space of the solution are presented. Related Articles | Metrics

Select

Periodic Solutions of Neutral Integro-Differential Equations with Infinite Delay Jiang Jiao; Xu Jianhua; Han Maoan Acta mathematica scientia,Series A. 2008, 28 (5):  897-905.  Abstract ( 2091 )   RICH HTML PDF (301KB) ( 1379 )   Save In this paper, by using the method of matrix measure and Schauder’s fixed-point theorem, the authors consider the existence and uniform stability of a unique periodic solution for neutral Volterra integro-differential equations with infinite delay, extend and improve the corresponding results. Related Articles | Metrics

Select

The Numbers of Spanning Trees in Some Graphs Chen Dong; Wang Weifan Acta mathematica scientia,Series A. 2008, 28 (5):  906-913.  Abstract ( 1616 )   RICH HTML PDF (260KB) ( 1205 )   Save A spanning tree in a connected graph G is a spanning subgraph of G that is a tree. In this paper, the authors determine precisely the numbers of spanning trees in some special graphs such as double-center wheels, double-handle fans, etc. Related Articles | Metrics

Select

The Isometric Embedding of Synclastic Simplexes to Euclidean Space and Applications Yang Dinghua Acta mathematica scientia,Series A. 2008, 28 (5):  914-922.  Abstract ( 1980 )   RICH HTML PDF (412KB) ( 1300 )   Save In this paper, by the matrix method, a necessary and sufficient condition for two n-dimensional synclastic simplexes to be able embedded in the n-dimensional Euclidean space is obtained, as well as for two group finite point sets. Then, by using the algebraic method which was introduced by Yang L. and Zhang J. Z., and the generalized isometric embedding theory, the generalized concept of metric addition is brought forward, a geometric inequality about the generalized metric addition is given, and the main result of Yang L. and Zhang J. Z. on Alexander conjecture is generalized, the higher dimensional Neuberg-Pedoe inequality generalized by Yang L. and Zhang J. Z. is generalized also. By these inequalities, a class of geometric inequalities about four simplexes is obtained, These imply some recent results in literature. Related Articles | Metrics

Select

A Fan Type Theorem for Heavy Cycles in Weighted Graphs Yu Rong;Hu Zhiquan Acta mathematica scientia,Series A. 2008, 28 (5):  923-928.  Abstract ( 1737 )   RICH HTML PDF (288KB) ( 1398 )   Save Let G=(V, E; w) be a weighted graph, and define the weighted degree dwG(v) of a vertex v in G as the sum of the weights of the edges incident with v. In this paper, the following theorem is proved: suppose G is a 2-connected weighted graph, where (i) w(xy)=w(yz) for every induced path xyz, and (ii) in every induced subgraph T of G isomorphic to K1,3 or K1,3+e, all the edges of T have the same weight and min{max{dwG(x), dwG(y)} : d(x,y) =2,x,y ∈ V(T)}≥ c/2, then G contains either a Hamilton cycle or a cycle of weight c at least. This respectively generalizes three theorems of Fan[5], Bedrossian et al[2] and Zhang et al[7]. Related Articles | Metrics

Select

On a Class of Elliptic Equation with Critical Potential and Indefinite Weights in R2 Zhang Guoqing; Liu Sanyang Acta mathematica scientia,Series A. 2008, 28 (5):  929-936.  Abstract ( 1615 )   RICH HTML PDF (314KB) ( 1115 )   Save The eigenvalue problem of a class of second order elliptic equation with critical potential and indefinite weights is investigated. Then, using critical point theory, Trudinger-Moser inequality and the properties of the first eigenvalue, the authors prove the existence of nontrivial solutions for a class of nonlinear elliptic equations with critical potential and indefinite weights in R2. Related Articles | Metrics

Select

On Some p6-Groups with p-Groups as Automorphism Groups Su Hong; Zhao Zhenhua; Qiu Dunyuan Acta mathematica scientia,Series A. 2008, 28 (5):  937-941.  Abstract ( 1483 )   RICH HTML PDF (226KB) ( 1101 )   Save In this paper, the authors give three groups of order p6 with p-groups as automorphism groups, and obtain their orders of automorphism groups.Here p denotes an odd prime. Related Articles | Metrics

Select

Stability of One-leg θ-methods for Volterra Delay Integral Equations Xu Yang; Zhao Jingjun Acta mathematica scientia,Series A. 2008, 28 (5):  942-944.  Abstract ( 1878 )   RICH HTML PDF (220KB) ( 1190 )   Save Stable properties of one-leg θ -methods for Volterra integral equations with a lagging argument is considered. It is proved numerical methods preserve corresponding stability of this system if θ=1. Furthermore, stability region for the backward Euler method is presented. Related Articles | Metrics

Select

The Extreme Points of a Class of Analytic Operator-valued Functions Peng Zhigang Acta mathematica scientia,Series A. 2008, 28 (5):  945-957.  Abstract ( 1629 )   RICH HTML PDF (304KB) ( 1251 )   Save Let H be a Hilbert space. B(H) denotes the Banach space of all bounded linear operators of H into H. Let T ={ f(z): f(z)=zI-∑∞n=2 znAn is analytic on the unit disk |z|<1, where the coefficients An are compact positive Hermitian operators of H into H and I denotes the identity operator on H, ∑∞n=2 n(An x, x) ≤ 1 for any x ∈ H with ∣|x|∣=1. In this paper the author investigates the extreme points of T . Related Articles | Metrics

Select

On Axion Systems for R0-algebras Huang Yisheng Acta mathematica scientia,Series A. 2008, 28 (5):  958-966.  Abstract ( 1239 )   RICH HTML PDF (305KB) ( 1188 )   Save In this paper the author gives some reduced axiom systems of R0-algebras, and shows that R0-algebras are equivalent to BCK-algebras satisfying some conditions. Related Articles | Metrics

Select

Flow-shop Scheduling Problem with Transportation Times and a Single Robot Shi Ling; Wen Jun Acta mathematica scientia,Series A. 2008, 28 (5):  967-970.  Abstract ( 1374 )   RICH HTML PDF (257KB) ( 1297 )   Save The paper considers the problem of scheduling jobs in a three-machine flow-shop to minimize the makespan. Between the completion of an operation and the beginning of the next operation of the same job, there is a time lag, which we refer to it as the transportation time. All transportation times have to be done by a single robot, which can perform at most one transportation at a time. New complexity results are derived for special case. Related Articles | Metrics

Select

Existence of Positive Solutions for a Class of Nonlinear Elliptic Equations Deng Zhiying; Huang Yisheng Acta mathematica scientia,Series A. 2008, 28 (5):  971-976.  Abstract ( 2015 )   RICH HTML PDF (286KB) ( 1262 )   Save In this paper, the authors discuss a class of elliptic equations by using the improved Hardy inequality and variational methods. The authors obtain the existence results of positive solutions under certain conditions. Related Articles | Metrics

Select

Backward Doubly Stochastic Differential Equations with Non-Lipschitz Coefficients Zhu Bo; Han Baoyan Acta mathematica scientia,Series A. 2008, 28 (5):  977-984.  Abstract ( 2204 )   RICH HTML PDF (292KB) ( 1347 )   Save A class of backward doubly stochastic differential equations (BDSDEs) are studied. The existence and uniqueness of solution to BDSDEs with non-Lipschitz coefficients is obtained,~and a comparison theorem to this kind of backward stochastic differential equations is showed. Related Articles | Metrics