用Hadamard方法构造惯性流形

本文用Ｈａｄａｍａｒｄ方法为一类带有非线性项Ｒ：Ｄ（Ａ）→Ｈ的无限维耗散动力系统建立惯性流形．在建立惯性流形的过程中，系统的一种“不变锥性质”被充分利用着．这里，对惯性流形存在性至关紧要的谱间隙条件是．     

拟周期时滞耗散半线性波方程的惯性流形

本文研究了具有拟周期外力作用的时滞波方程解的长时间性态,利用斜积半流方法,在扩展相空间中将非自治系统提升成自治系统,利用算子半群理论及Lyapunov-Perron方法在一定的谱间隙条件和充分小的时滞假设下,证明了拟周期半线性时滞波方程惯性流形的存在性.     

On the univalence of an integral operator defined by Hadamard product

In this paper, we introduce a new general integral operator defined by the Hadamard product. Furthermore, we obtained new sufficient conditions for this operator to be univalent in the open unit disk.     

由GA-凸函数的Hadamard型不等式生成的差值的估计

考虑由GA-凸函数的Hadamard型不等式右端部分生成的差值,将这个差值表示为涉及导函数的积分,然后结合Grüss积分不等式、Hlder积分不等式以及凸函数的定义给出这个差值的估计.     

Abstract Cauchy Problems for Quasi-Linear Evolution Equations in the Sense of Hadamard

This paper is devoted to the well-posedness of abstract Cauchyproblems for quasi-linear evolution equations. The notion ofHadamard well-posedness is considered, and a new type of stabilitycondition is introduced from the viewpoint of the theory offinite difference approximations. The result obtained here generalizesnot only some results on abstract Cauchy problems closely relatedwith the theory of integrated semigroups or regularized semigroupsbut also the Kato theorem on quasi-linear evolution equations.An application to some quasi-linear partial differential equationof weakly hyperbolic type is also given. 2000 Mathematics SubjectClassification 34G20, 47J25 (primary), 47D60, 47D62 (secondary).     

多因素最优化的重大突破——简记正交表方法的发展史(下半篇)

多因素最优化的重大突破——简记正交表方法的发展史（下半篇）张里千张建方（中国科学技术大学研究生院，北京，１０００３９）（四）正交法的发展进程至少有以下三方面的原因，就笔者的认识与了解所及、记载下正交法的发展过程。不当之处，欢迎专家补充、批评与指正。...     

Construction of the ground state in nonrelativistic QED by continuous flows

For a nonrelativistic hydrogen atom minimally coupled to the quantized radiation field we construct the ground state projection Pgs by a continuous approximation scheme as an alternative to the iteration scheme recently used by Fröhlich, Pizzo, and the first author [V. Bach, J. Fröhlich, A. Pizzo, Infrared-finite algorithms in QED: The groundstate of an atom interacting with the quantized radiation field, Comm. Math. Phys. (2006), doi: 10.1007/s00220-005-1478-3]. That is, we construct Pgs=limt→∞Pt as the limit of a continuously differentiable family (Pt)_t?0 of ground state projections of infrared regularized Hamiltonians Ht. Using the ODE solved by this family of projections, we show that the norm of their derivative is integrable in t which in turn yields the convergence of Pt by the fundamental theorem of calculus.     

Method of lines solutions of the parabolic inverse problem with an overspecification at a point

The present work is motivated by the desire to obtain numerical solution to a quasilinear parabolic inverse problem. The solution is presented by means of the method of lines. Method of lines is an alternative computational approach which involves making an approximation to the space derivatives and reducing the problem to a system of ordinary differential equations in the variable time, then a proper initial value problem solver can be used to solve this ordinary differential equations system. Some numerical examples and also comparison with finite difference methods will be investigated to confirm the efficiency of this procedure.     

Jacobi elliptic function solutions of the (1 + 1)‐dimensional dispersive long wave equation by Homotopy Perturbation Method

In this article, we try to obtain approximate Jacobi elliptic function solutions of the (1 + 1)‐dimensional long wave equation using Homotopy Perturbation Method. This method deforms a difficult problem into a simple problem which can be easily solved. In comparison with HPM, numerical methods leads to inaccurate results when the equation intensively depends on time, while He's method overcome the above shortcomings completely and can therefore be widely applicable in engineering. As a result, we obtain the approximate solution of the (1 + 1)‐dimensional long wave equation with initial conditions. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2008