A model of image processing for anisotropic diffusion driven by diffusion tensors is investigated. An implicit difference scheme is constructed. A large sparse matrix with 13 diagonals is formed with which general iterative methods don't work well. With algebraic multi-grid method (AMG), linear system of equations are solved.Numerical experiments are shown.

Particular solution BEM is used to solve three-dimensional Pennes equation.The solution is devided into the common solution of Poisson equation and the particular solution.The common solution is solved by BEM while the particular solution is given by the method of separation of variables.Temperature and heatflux are computed piecewisely in each time step and then the value on the nods in the field is computed.Numerical simulation of cancer hypothermia is given based on this method.