J.C.R.Claeyssen and H.F. Campos Velho (1994): Initialization Using Non-Modal Matrix Approach, Bulletin of the Brazilian Society for Computing and Applied Mathematics, 5, No. 1, series II, pp. 39-50.

Abstract: Non-modal numerical techniques are useful for initialization of limited area models where normal modes are not easily avaliable. Here we use a time-domain matrix approach to the DYNAMO model which allows filtering out of high-frequency components of initial fields. This will allow us to formulate a non-linear matrix differential equation which has a block circulant structure.