| The dimensional reduction method for solving boundary value problem of heat conduction in a three-dimensional laminated plate by replacing them with systems of equations in 2-dimensional space is investigated. It is proved that the existence and uniqueness for the exact solution and the dimensionally reduced solution of the problem if the input data on the faces are in some class of functions. Finally, the modeling error between and in is precisely estimated as and are fixed, where the norm is equivalent to the Soblev norm . |