Abstract: In this paper the existence and uniqueness of solutions of boundary value problemsεy"=f(t,y,e) L(y(0),y'(0,ε=0, R(y(1),y'(1),ε=0) (which contains the Robin's problem) is discussed by using the upper and lower solution. In addition,the asymptotic estimation of the solution is given as well.

Key words: biomagnetic fluid, blood, stretching walls, porous medium, electromagnetic hyperthermia