ولی اله غفاری

‎The Lyapunov stability theory has been a well-known and powerful method for justifying the solution property and also stability analysis of an equilibrium point in the nonlinear systems‎. ‎The stability notions may usually be expressed in terms of some norm functions in the conventional Lyapunov stability theory‎. ‎In this paper‎, ‎the boundedness and stability concepts would been investigated within a defined set instead of the equilibrium point‎. ‎Then‎, ‎based on the measure functions concept‎, ‎the boundedness and also stability properties of the solution will be extended to develop a modified stability theory in the nonlinear systems‎.