A quasi‐static boundary value problem in multi‐surface elastoplasticity: part 2—numerical solution

Multi‐yield elastoplasticity models a material with more than one plastic state and hence allows for refined approximation of irreversible deformations. Aspects of the mathematical modelling and a proof of unique existence of weak solutions can be found in part I of this paper (Math. Models Methods Appl. Sci. 2004). In this part II we establish a canonical time–space discretization of the evolution problem and present various algorithms for the solving really discrete problems. Based on a global Newton–Raphson solver, we carefully study and solve elementwise inner iterations. Numerical examples illustrate the model and its flexibility to allow for refined hysteresis curves. Copyright © 2005 John Wiley & Sons, Ltd.     

Variational inequalities with operator solutions

The aim of the present paper is to give a new kind of point of view in the theory of variational inequalities. Our approach makes possible the study of both scalar and vector variational inequalities under a great variety of assumptions. One can include here the variational inequalities defined on reflexive or nonreflexive Banach spaces, as well as the vector variational inequalities defined on topological vector spaces.     

乘积G-凸空间内的G_B-优化映象的极大元及其应用(Ⅱ)

通过应用G＿凸空间的乘积空间内一族GB＿优化映象的极大元的存在定理,在G＿凸空间的非紧设置下证明了某些重合点定理,Fan＿Browder型不动点定理和极小极大不等式组的解的存在性定理·　这些定理改进和推广了文献中许多重要的已知结果·     

L 1→ L q Poincaré Inequalities for 0 < q < 1 Imply Representation Formulas

Given two doubling measures μ and ν in a metric space (S, ρ) of homogeneous type, let B ₀⊂S be a given ball. It has been a well-known result by now (see [1–4]) that the validity of an L ¹→L ¹ Poincaré inequality of the following form: for all metric balls B⊂B ₀⊂S, implies a variant of representation formula of fractional integral type: for ρ-a.e. x∈B ₀, One of the main results of this paper shows that an L ¹ to L ^q Poincaré inequality for some 0 < q < 1, i.e., for all metric balls B⊂B ₀, will suffice to imply the above representation formula. As an immediate corollary, we can show that the weak-type condition, also implies the same formula. Analogous theorems related to high-order Poincaré inequalities and Sobolev spaces in metric spaces are also proved. Received December 27, 2000, Accepted May 28, 2001     

The phase transition in the discrete Gaussian chain with 1/r 2 interaction energy

We exhibit a phase transition from a rough high-temperature phase to a rigid (localized) low-temperature phase in the discrete Gaussian chain with 1/r ² interaction energy. This transition is related to a localization transition in the ground state for a quantum mechanical particle in a one-dimensional periodic potential, coupled to quantum 1/f noise.This paper is dedicated to J. L. Lebowitz on the occasion of his 60th birthday     

Solution of Finite-Dimensional Variational Inequalities Using Smooth Optimization with Simple Bounds

The variational inequality problem is reduced to an optimization problem with a differentiable objective function and simple bounds. Theoretical results are proved, relating stationary points of the minimization problem to solutions of the variational inequality problem. Perturbations of the original problem are studied and an algorithm that uses the smooth minimization approach for solving monotone problems is defined.     

A descent algorithm for solving monotone variational inequalities and monotone complementarity problems

The paper provides a descent algorithm for solving certain monotone variational inequalities and shows how this algorithm may be used for solving certain monotone complementarity problems. Convergence is proved under natural monotonicity and smoothness conditions; neither symmetry nor strict monotonicity is required.The author is grateful to two anonymous referees for their very valuable comments on an earlier draft of this paper.     

On self-reciprocal polynomials

In this paper we establish a sharp result concerning integral mean estimates for self-reciprocal polynomials.     

Best approach regions for potential spaces

We characterize the approach regions so that the non-tangential maximal function is of weak-type on potential spaces, for which we use a simple argument involving Carleson measure estimates.

     

Complementarity Problems and Variational Inequalities. A Unified Approach of Solvability by an Implicit Leray-Schauder Type Alternative

In several recent papers we obtained existence theorems for complementarity problems and variational inequalities using for each of them a particular notion of exceptional family of elements. Now, in this paper we introduce a new notion of exceptional family of elements. This notion is based on an Implicit Leray-Schauder Alternative. By this new notion we obtain a unification of the study of solvability of complementarity problems and of variational inequalities. The paper is finished with a section dedicated to variational inequalities with δ-pseudomonotone operators.