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In a preceding paper we have presented a unified view of the identification methods dedicated to adaptive sequential systems. In this paper, we develop the resolution technique based on genetic simulation. We analyse the various parameters of such an approach, then, we propose a tool intended to demonstrate the interest of this new approach, and finally we present some differential identification experiments conducted with this tool. Copyright © 2001 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper presents a new computer algorithm for generating spatially-correlated random fields. Such fields are often encountered in hydrology and hydrogeology and in the earth sciences and used as inputs for Monte Carlo simulations. The algorithm is designed by using a multilevel grid strategy and combining the matrix decomposition (MD) method and the screening sequential simulation (SSS) method. The idea originates from the facts: (i) the MD method accounts for all possible nodal correlation values and hence the accuracy of the method is high, but it can be extremely computationally intensive for fine meshes with large number of nodes, and (ii) the SSS method is more efficient because a small search neighbourhood for conditioning can be used due to the screening effect of measurements, however, for large separation distances, correlation values from the SSS method is significantly inferior to the values obtained by the MD method. Numerical examples are presented to demonstrate the new method. It is shown that the presented method is much more efficient than the MD method and more accurate than the SSS method. The new algorithm is also versatile: it can directly simulate fields of irregular geometry without additional efforts. Copyright © 2003 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The use of micromechanically based constitutive equations for contact interfaces leads to technically relevant parameters to ill-conditioned finite-element equations. In the paper an augmented Lagrangian technique is employed to overcome this difficulty and to provide a good converging algorithm. [ABSTRACT FROM AUTHOR]