We study the algebra An, the basis of the Hilbert space Hn in terms of θ functions of the positions of n solitons. Then we embed the Heisenberg group as the quantum operator factors in the representation of the transfer matrice of various integrable models. Finally we generalize our result to the generic θ case. PACS: 11.90.+t, 11.25.-w

A new operator is considered, allowing compact formulae and proofs in the context of the derivation of a transfer matrix with respect to another matrix. The problem of the parametric sensitivity matrix calculation is chosen for illustration. It consists in deriving a Multiple Input Multiple Output transfer function with respect to a parametric matrix and is central in robust control theory. Eff...

A numerical model has been developed for the large-scale simulation of solute transport in discretelyfractured porous media. A generic finite elements code, MEF++, has been used to account for simultaneous flow and transport in 2D fracture and 3D porous medium elements. Equations for the fractures and the porous medium are solve separately but are coupled with a mass transfer term. This mass tr...