一些组合地图新算法的实现

本文主要讨论组合地图列举问题.刘的一部专著中提出了一个判定两个地图是否同构的算法.该算法的时间复杂度为O(m2),其中m为下图的规模.在此基础上,本文给出一个用于地图列举以及进而计算任意连通下图的地图亏格分布的通用算法.本文所得结果比之前文献中所给结果更优.     

Propagation of traveling wave solutions for nonlinear evolution equation through the implementation of the extended modi ed direct algebraic method

In this work,di erent kinds of traveling wave solutions and uncategorized soliton wave solutions are obtained in a three dimensional(3-D)nonlinear evolution equations(NEEs)through the implementation of the modi ed extended direct algebraic method.Bright-singular and dark-singular combo solitons,Jacobi's elliptic functions,Weierstrass elliptic functions,constant wave solutions and so on are attained beside their existing conditions.Physical interpretation of the solutions to the 3-D modi ed KdV-Zakharov-Kuznetsov equation are also given.     

Sign-based Test for Mean Vector in High-dimensional and Sparse Settings

In this article, we introduce a robust sparse test statistic which is based on the maximum type statistic. Both the limiting null distribution of the test statistic and the power of the test are analysed. It is shown that the test is particularly powerful against sparse alternatives. Numerical studies are carried out to examine the numerical performance of the test and to compare it with other tests available in the literature. The numerical results show that the test proposed significantly outperforms those tests in a range of settings, especially for sparse alternatives.     

Multiple Positive Solutions for One Dimensional Third Order p-Laplacian Equations with Integral Boundary Conditions

In this paper,we consider the one dimensional third order p-Laplacian equation■u^′′(0)=0.By using kernel functions and the Avery-Peterson fixed point theorem,we establish the existence of at least three positive solutions.     

中国数学会举行第十次全国代表大会

中国数学会第十次全国代表大会暨2007学术年会11月2日在北京航空航天大学开幕,这是中国数学会历史上规模最大的一次全国代表大会.教育部副部长吴启迪、中国科协书记处书记冯长根、北京航空航天大学校长李未及中科院、科技部等单位的相关领导、嘉宾出席开幕式.     

Bayesian Approach for Recovering Piecewise Constant Viscoelasticity from MRE Data

This paper deals with an inverse problem for recovering the piecewise constant viscoelasticity of a living body from MRE(Magnetic Resonance Elastography)data.Based on a scalar partial differential equation whose solution can approximately simulate MRE data,our inverse coefficient problem is considered as a statistical inverse problem of reconstructing the posterior distribution of unknown viscoelastic modulus.For sampling this distribution,one usually can use the Metropolis-Hastings Markov chain Monte Carlo(MHMCMC)algorithm.However,without an appropriate"proposal"distribution given artificially,the MH-MCMC algorithm is hard to draw samples efficiently.To avoid this,a so-called slice sampling algorithm is introduced in this paper and applied for solving our problem.The performance of these statistical inversion algorithms is numerically tested basing on simulated data.     

RIEMANN-HILBERT PROBLEMS AND SOLITON SOLUTIONS OF NONLOCAL REVERSE-TIME NLS HIERARCHIES

The paper aims at establishing Riemann-Hilbert problems and presenting soliton solutions for nonlocal reverse-time nonlinear Schrodinger(NLS) hierarchies associated with higher-order matrix spectral problems.The Sokhotski-Plemelj formula is used to transform the Riemann-Hilbert problems into Gelfand-Levitan-Marchenko type integral equations.A new formulation of solutions to special Riemann-Hilbert problems with the identity jump matrix,corresponding to the reflectionless inverse scattering transforms,is proposed and applied to construction of soliton solutions to each system in the considered nonlocal reversetime NLS hierarchies.     

Solitary Wave Solutions of Delayed Coupled Higgs Field Equation

This paper is devoted to the study of the solitary wave solutions for the delayed coupled Higgs field equation{vtt-uxx-αu+βf*u|u|²-2uv-τu(|u|²)x=0 vtt+vxx-β(|u|^x)xx=0.We first establish the existence of solitary wave solutions for the corresponding equation without delay and perturbation by using the Hamiltonian system method.Then we consider the persistence of solitary wave solutions of the delayed coupled Higgs field equation by using the method of dynamical system,especially the geometric singular perturbation theory,invariant manifold theory and Fredholm theory.According to the relationship between solitary wave and homoclinic orbit,the coupled Higgs field equation is transformed into the ordinary differential equations with fast variables by using the variable substitution.It is proved that the equations with perturbation also possess homoclinic orbit,and thus we obtain the existence of solitary wave solutions of the delayed coupled Higgs field equation.     

RIEMANN-HILBERT PROBLEMS AND SOLITON SOLUTIONS OF NONLOCAL REVERSE-TIME NLS HIERARCHIES

The paper aims at establishing Riemann-Hilbert problems and presenting soliton solutions for nonlocal reverse-time nonlinear Schrodinger(NLS) hierarchies associated with higher-order matrix spectral problems.The Sokhotski-Plemelj formula is used to transform the Riemann-Hilbert problems into Gelfand-Levitan-Marchenko type integral equations.A new formulation of solutions to special Riemann-Hilbert problems with the identity jump matrix,corresponding to the reflectionless inverse scattering transforms,is proposed and applied to construction of soliton solutions to each system in the considered nonlocal reversetime NLS hierarchies.     

Indefinite Least Squares Problem with Quadratic Constraint and Its Condition Numbers

In this paper,we consider the indefinite least squares problem with quadratic constraint and its condition numbers.The conditions under which the problem has the unique solution are first presented.Then,the normwise,mixed,and componentwise condition numbers for solution and residual of this problem are derived.Numerical example is also provided to illustrate these results.     

关于广义双拟变分不等式和拟变分不等式

研究了一类广义双拟变分不等式和广义拟变分不等式解的存在性，推广、改进、统一了一些近期的相关结果．     

Generalized Bi quasi variational Inequalities in Locally Convex Topological Vector Spaces

§１．　ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｒｏｕｇｈｏｕｔｔｈｉｓｐａｐｅｒ,Φｄｅｎｏｔｅｓｅｉｔｈｅｒｔｈｅｒｅａｌｆｉｅｌｄｏｒｔｈｅｃｏｍｐｌｅｘｆｉｅｌｄ．Ｆｏｒａｎｏｎｅｍｐ－ｔｙｓｅｔＹ,２ＹｗｉｌｌｓｔａｎｄｆｏｒｔｈｅｆａｍｉｌｙｏｆａｌｌｎｏｎｅｍｐｔｙｓｕｂｓｅｔｓｏｆＹ．ＬｅｔＥ,ＦｂｅｖｅｃｔｏｒｓｐａｃｅｓｏｖｅｒΦ,〈,〉：Ｆ×Ｅ→Φｂｅａｂｉｌｉｎｅａｒｆｕｎｃｔｉｏｎａｌ,ａｎｄＸｂｅａｎｏｎｅｍｐｔｙｓｕｂｓｅｔｏｆＥ．Ｇｉｖｅｎａｍｕｌ－ｔｉ－ｖａｌｕｅｄｍａｐｐ…     

Generalized bi-quasi-variational inequalities for quasi-pseudo-monotone type II operators on compact sets

In this paper, the authors prove some existence results of solutions for a new class of generalized bi-quasi-variational inequalities (GBQVI) for quasi-pseudo-monotone type II and strongly quasi-pseudo-monotone type II operators defined on compact sets in locally convex Hausdorff topological vector spaces. In obtaining these results on GBQVI for quasi-pseudo-monotone type II and strongly quasi-pseudo-monotone type II operators, we shall use Chowdhury and Tan’s generalized version [3] of Ky Fan’s minimax inequality [7] as the main tool.     

Generalized bi-Quasi-Variational Inequalities for Upper Hemi-Continuous Operators in non-Compact Settings

By using the concept of escaping sequences introduced by Border [2], existence theorems on generalized bi-quasi-variational inequalities for F-semi-monotone (re- spectively, bi-quasi-semi-monotone) operators are obtained in non-compact set- tings. As application, an existence theorem on generalized bi-complementarity problem for F-semi-monotone (respectively, bi-quasi-semi-monotone) operator is given in non-compact setting.     

Generalized bi-quasi-variational inequalities for quasi-pseudo-monotone type I operators on compact sets

In this paper, the authors prove some existence results of solutions for a new class of generalized bi-quasi-variational inequalities (GBQVI) for quasi-pseudo-monotone type I operators defined on compact sets in locally convex Hausdorff topological vector spaces. In obtaining these results on GBQVI for quasi-pseudo-monotone type I operators, we shall use Chowdhury and Tan’s generalized version [3] of Ky Fan’s minimax inequality [7] as the main tool. Mohammad S.R. Chowdhury: The project was done while the author was visiting Dalhousie University in the Summer-2006. Kok-Keong Tan: This project was partially supported by NSERC of Canada under Grant A-8096.     

广义双拟变分不等式的推广*

本文引出和研究了一类新型双拟变分不等式解的存在性问题.本文的结果统一、改进和发展了有关变分不等式问题许多最新的结果.     

同向单形到欧氏空间的等距嵌入及其应用

该文利用矩阵的方法, 获得了两个同向的 n 维单形同时等距嵌入 Eⁿ 维欧氏空间的一个充分必要条件是: 对于预给(n+1)²个距离,满足一组具有行列式形式的不等式组det(△_k)<0, 由此可以得到两组等数量的有限点集合到 Eⁿ 维欧氏空间中等长嵌入的一个充分必要条件. 然后利用杨路和张景中引进的代数方法, 应用广义等距嵌入定理, 提出了关于两组两个完全同向的 n 维单形“广义度量加”的概念, 并且证明了涉及“广义度量加”的一个几何不等式, 它推广了杨路和张景中关于Alexander猜想的结果. 同时我们将杨路和张景中关于Neuberg-Pedoe不等式的高维推广形式推广到两组两个完全同向的 n 维单形中, 获得了涉及四个单形的一类几何不等式, 它们蕴含近期诸多文献的主要结果.     

General KKM Theorem with Applications to Minimax and Variational Inequalities

In this paper, a general version of the KKM theorem is derived by using the concept of generalized KKM mappings introduced by Chang and Zhang. By employing our general KKM theorem, we obtain a general minimax inequality which contains several existing ones as special cases. As applications of our general minimax inequality, we derive an existence result for saddle-point problems under general setting. We also establish several existence results for generalized variation inequalities and generalized quasi-variational inequalities.     

Generalized Vector Variational and Quasi-Variational Inequalities with Operator Solutions

In a recent paper, Domokos and Kolumbán introduced variational inequalities with operator solutions to provide a suitable unified approach to several kinds of variational inequality and vector variational inequality in Banach spaces. Inspired by their work, in this paper, we further develop the new scheme of vector variational inequalities with operator solutions from the single-valued case into the multi-valued one. We prove the existence of solutions of generalized vector variational inequalities with operator solutions and generalized quasi-vector variational inequalities with operator solutions. Some applications to generalized vector variational inequalities and generalized quasi-vector variational inequalities in a normed space are also provided.     

Generalized Chow Forms and Reduction of Semi-Stable Varieties

In this note, by using the method of S. Zhang [1], we obtain the local version of a theorem of BGS [2] which links Faltings heights of projective varieties with the Philippon heights for the corresponding generalized Chow points. By the stable reduction theorem of S. Zhang [1], we prove that Chow semistabilities and generalized Chow semistabilities are the same. Received March 12, 1996, Accepted March 10, 1997