We consider the asymptotic stability problems by Lyapunov functionals V for a class of functional differential equations with impulses of the form x′(t)=f(t,xt), x∊Rn, t≧t0, t≠tk; △x=Ik(t,x(t−)), t=tk, k∊Z+. Some new asymptotic stability results are presented by using an idea originated by Burton and Makay [6] and developed by Zhang [1]. We generalize some known results about impulsive functional differential equations in the literature in which we only require the derivative of V to be negative definite on a sequence of intervals In=[sn,ξn] which may or may not be contained in the sequence of impulsive time intervals [tn,tn+1).
[1] Anokhin, A. V. Berezansky, L. Braverman, E. 1995 Exponential stability of linear delay impulsive differential equations J. Math. Anal. Appl. 193 923–941 .
[2] Bainov, D. D. Covachev, V. Stamova, I. 1994 Stability under persistent disturbances of impulsive differential-difference equations of neutral type J. Math. Anal. Appl. 187 790–808 .
[3] Ballinger, G. Liu, X. 1999 Existence and uniqueness results for impulsive delay differential equations Dynamics of Continuous, Discrete and Impulsive Systems 5 579–591.
[4] Burton, T. A. 1978 Uniform asymptotic stability in functional differential equations Proc. Amer. Math. Soc. 68 195–199 .
[5] Burton, T. A. 1985 Stability and Periodic Solutions of Ordinary and Functional Differential Equations Academic Press Orlando.
[6] Burton, T. A. Hatvani, L. 1989 Stability theorems for nonautonomous functional differential equations by Lyapunov functional Tohoku Math. J. 41 65–104 .
[7] Burton, T. A. Hatvani, L. 1990 On nonuniform asymptotic stability for nonautonomous functional differential equations Differential and Integral Equations 2 285–293.
[8] Burton, T. A. Makay, G. 1994 Asymptotic stability for functional differential equations Acta Math. Hungar. 65 243–251 .
[9] Hale, J. K. 1997 Theory of Functional Differential Equations Springer-Verlag New York.
[10] Hatvani, L. 1997 Annulus arguments in the stability theory for functional differential equations Differential and Integral Equations 10 975–1002.
[11] Hatvani, L. 2002 On the asymptotic stability for nonautonomous functional differential equations by Lyapunov functionals Trans. Amer. Math. Soc. 354 3555–3571 .
[12] Kato, J., A conjecture in Lyapunov method for functional differential equations, preprint.
[13] Krasovskii, N. N. 1959 Some Problems in the Theory of Stability of Motion Gosudarstv. Izdat. Fiz. Mat. Lit. Moscow in Russian.
[14] Shen, Jianhua 1996 Existence and uniqueness of solutions for impulsive functional differential equations on the PC space with applications Acta Sci. Nat. Uni. Norm. Hunan 24 285–291 in Chinese.
[15] Shen, J. Li, J. 2005 Impulsive control for stability of Volterra functional differential equations J. for Anal. and its Appl. 24 721–734.
[16] Shen, J. Luo, Z. 1999 Impulsive stabilization of functional differential equations via Lyapunov functionals J. Math. Anal. Appl. 240 1–15 .
[17] Yoshizawz, T. 1966 Stability by Lyapunov's Second Method Math. Soc. Japan Tokyo.
[18] Zhang, B. 1995 Asymptotic stability in functional differential equations by Lyapunov functionals Trans. Amer. Math. Soc. 347 1375–1382 .