V. A. Ivanov, M. Ya. Marusina, A. V. Flegontov
Saint-Petersburg State Institute of Fine Mechanics and Optics (Technical University)
A method of reduction of the artefact influence on MR-images
using the theory of invariants is considered. This task is reduced to synthesis
of groups of measuring transformations leaving dimension without distortions,
i.e. solving the problem of invariant approximation of a given function
by functions of less variables. The construction of allowable groups, calculation
of invariants and functions using the invariants are described, examples
are given.