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Mesh r-adaptation for unilateral contact problems

Pierre Béal, Jonas Koko, Rachid Touzani (2002)

International Journal of Applied Mathematics and Computer Science

We present a mesh adaptation method by node movement for two-dimensional linear elasticity problems with unilateral contact. The adaptation is based on a hierarchical estimator on finite element edges and the node displacement techniques use an analogy of the mesh topology with a spring network. We show, through numerical examples, the efficiency of the present adaptation method.

Mesh Refinement For Stabilized Convection Diffusion Equations

B. Achchab, M. El Fatini, A. Souissi (2010)

Mathematical Modelling of Natural Phenomena

We derive a residual a posteriori error estimates for the subscales stabilization of convection diffusion equation. The estimator yields upper bound on the error which is global and lower bound that is local

Mesh-independence and preconditioning for solving parabolic control problems with mixed control-state constraints

Michael Hintermüller, Ian Kopacka, Stefan Volkwein (2009)

ESAIM: Control, Optimisation and Calculus of Variations

Optimal control problems for the heat equation with pointwise bilateral control-state constraints are considered. A locally superlinearly convergent numerical solution algorithm is proposed and its mesh independence is established. Further, for the efficient numerical solution reduced space and Schur complement based preconditioners are proposed which take into account the active and inactive set structure of the problem. The paper ends by numerical tests illustrating our theoretical findings and...

Mesh-independence and preconditioning for solving parabolic control problems with mixed control-state constraints

Michael Hintermüller, Ian Kopacka, Stefan Volkwein (2008)

ESAIM: Control, Optimisation and Calculus of Variations

Optimal control problems for the heat equation with pointwise bilateral control-state constraints are considered. A locally superlinearly convergent numerical solution algorithm is proposed and its mesh independence is established. Further, for the efficient numerical solution reduced space and Schur complement based preconditioners are proposed which take into account the active and inactive set structure of the problem. The paper ends by numerical tests illustrating our theoretical findings and comparing...

Meshless Polyharmonic Div-Curl Reconstruction

M. N. Benbourhim, A. Bouhamidi (2010)

Mathematical Modelling of Natural Phenomena

In this paper, we will discuss the meshless polyharmonic reconstruction of vector fields from scattered data, possibly, contaminated by noise. We give an explicit solution of the problem. After some theoretical framework, we discuss some numerical aspect arising in the problems related to the reconstruction of vector fields

Meta-optimization of bio-inspired algorithms for antenna array design

Virgilio Zúñiga-Grajeda, Alberto Coronado-Mendoza, Kelly Joel Gurubel-Tun (2018)

Kybernetika

In this article, a technique called Meta-Optimization is used to enhance the effectiveness of bio-inspired algorithms that solve antenna array synthesis problems. This technique consists on a second optimization layer that finds the best behavioral parameters for a given algorithm, which allows to achieve better results. Bio-inspired computational methods are useful to solve complex multidimensional problems such as the design of antenna arrays. However, their performance depends heavily on the...

Method of fundamental solutions for biharmonic equation based on Almansi-type decomposition

Koya Sakakibara (2017)

Applications of Mathematics

The aim of this paper is to analyze mathematically the method of fundamental solutions applied to the biharmonic problem. The key idea is to use Almansi-type decomposition of biharmonic functions, which enables us to represent the biharmonic function in terms of two harmonic functions. Based on this decomposition, we prove that an approximate solution exists uniquely and that the approximation error decays exponentially with respect to the number of the singular points. We finally present results...

Currently displaying 101 – 120 of 362