An approximation theory for the estimation of parameters in degenerate Cauchy problems (Q1192754)

The paper gives an abstract approximation framework for the identification of linear degenerate systems based on ideas concerning the Trotter-Kato approximation theorem for linear semigroups. With respect to style and notation the paper is related to the well-known framework of H. T. Banks and coauthors on inverse problems for distributed parameter systems. In a Hilbert space setting linear degenerate distributed systems are considered and well-posedness and approximation results are established. An essential part of the paper is devoted to parabolic systems, where the theoretical and approximation ideas developed in a more general context may be applied to specific estimation problems. There are presented numerical results for a parabolic example with a triple of unknown coefficient functions.