Interval criteria for oscillation of a forced impulsive differential equation with Riemann–Stieltjes integral

In this paper, both El-Sayed type and Kamenev type oscillation criteria for a forced impulsive differential equation with Riemann–Stieltjes integral are established. By using a generalized El-Sayed type function and Kong’s technique in terms of the number of impulse moments on a series of intervals, we not only drop the restriction on the impulse constants ckck and dkdk that dk≥ckdk≥ck in the literature, but also extend some existing results to the case of Riemann–Stieltjes integral and improve some results in the case of Riemann integral. Two examples are also considered to illustrate the main results.