Existence of Positive Solutions for Singular Second-order<Emphasis Type="Italic">m</Emphasis>-Point Boundary Value Problems

Abstract   The singular second-order m-point boundary value problem

An existence theorem of Walrasian equilibrium

The purpose of this note is to establish an existence theorem for Walrasian equilibrium under weaker conditions.     

On reductions for the Steiner Problem in Graphs

Several authors have demonstrated how reductions can be used to improve the efficiency with which the Steiner Problem in Graphs can be solved. Previous reduction algorithms have been largely ad hoc in nature. This paper uses a theory of confluence to show that, in many cases, all maximal reduction sequences are equivalent, gaining insights into the design of reduction algorithms that obtain a maximum degree of reduction.     

SOURCE－TYPE SOLUTIONS OF A QUASILINEAR DEGENERATE PARABOLIC EQUATION WITH ABSORPTION

ＳＯＵＲＣＥ－ＴＹＰＥ ＳＯＬＵＴＩＯＮＳ ＯＦ Ａ ＱＵＡＳＩＬＩＮＥＡＲ ＤＥＧＥＮＥＲＡＴＥ ＰＡＲＡＢＯＬＩＣ ＥＱＵＡＴＩＯＮ ＷＩＴＨ ＡＢＳＯＲＰＴＩＯＮ￥ＺＨＡＯＪＵＮＮＩＮＧＡｂｓｔｒａｃｔ：Ｔｈｅｅｘｉｓｔｅｎｃｅａｎｄｎｏｎｅｘ...     

MULTIPLE POSITIVE SOLUTIONS FOR A FOURTH-ORDER NONLINEAR EIGENVALUE PROBLEM

In this paper, by using the Guo-Krasnoselskii’s fixed-point theorem, we establish the existence and multiplicity of positive solutions for a fourth-order nonlinear eigenvalue problem. The corresponding examples are also included to demonstrate the results we obtained.     

ALMOST GLOBAL EXISTENCE OF DIRICHLETINITIAL-BOUNDARY VALUE PROBLEM FORNONLINEAR ELASTODYNAMIC SYSTEMOUTSIDE A STAR-SHAPED DOMAIN

This paper deals with the mixed initial-boundary value problem of Dirichlet type for the nonlinear elastodynamic system outside a star-shaped domain. The almost global existence of solution with small initial data to this problem is proved and a lower bound for the lifespan of solutions is given.     

一类新的求解P_*(κ)阵线性互补问题的多项式内点算法

利用核函数及其性质,对P_*(k)阵线性互补问题提出了一种新的宽邻域不可行内点算法.对核函数作了一些适当的改进,所以是不同于Peng等人介绍的自正则障碍函数.最后证明了算法具有近似O((1+2k)n3/4log(nμ~0)/ε)多项式复杂性,是优于传统的基于对数障碍函数求解宽邻域内点算法的复杂性.     

Novel procedure for complete in-plane composite characterization using a single T-shaped specimen

This paper deals with the direct identification of the in-plane elastic properties of orthotropic composite plates from heterogeneous strain fields. The shape of the tested specimen is that of a T subjected to a complex stress state. As a result, the entire set of unknown parameters is directly involved in the strain and displacement responses of the sample. No exact analytical solution is available for such a geometry, and a specific strategy is used to identify the different stiffness components from the whole-field displacements measured over the tested specimen with a suitable optical method. The paper focuses mainly on the experimental aspects of the procedure, and an example of mechanical characterization of a fabric-reinforced composite plate is given.     

Investigation and application of point implicit Runge–Kutta methods to inviscid flow problems

We derive and investigate point implicit Runge–Kutta methods to significantly improve the convergence rate to approximate steady‐state solutions of inviscid flows. It turns out that the point implicit Runge–Kutta can be interpreted as a preconditioned explicit Runge–Kutta method, where the preconditioner arises naturally as local derivative of the residual function. Moreover, many preconditioners suggested in the literature so far are identified as special case of our general ansatz. Conditions will be formulated such that explicit Runge–Kutta methods with local time stepping are equivalent to point implicit methods. In numerical examples, we will demonstrate the improved convergence rates. Copyright © 2011 John Wiley & Sons, Ltd.