(2+1)-DIMENSIONAL MODELS WITH VIRASORO-TYPE SYMMETRY ALGEBRA

According to a theory proposed in a previous paper by Lou and Hu, starting from a realization of a Virasoro-type symmetry algebra, we can obtain various (2 + 1)-dimensional integrable models under the condition that the models possess the infinitely dimensional Virasoro-type symmetry algebra. An explicit realization of the generalized Virasoro-type symmetry algebra is used to obtain concrete invariant models. A set of equations which possesses the same infinite dimensional Kac-Moody-Virasaro type Lie point symmetry algebra as that of the Kadomtsev-Petviashvilli equation is given.