In this paper, the problem of periodic solutions is studied for Liénard equations with
anindefinite singularity x′′(t)+ f (x (t)) x′(t)+ φ (t) xm (t)− α (t) x μ (t)= 0, where f:(0,+∞)→ R …

In this paper, the problem of periodic solutions is studied for second order differential
equations with indefinite singularities x ″(t)+ f (x (t)) x′(t)+ φ (t) xm (t)− α (t) x μ (t)+ β (t) xy …

In this paper, we study the existence of periodic solutions of the Liénard equation with a
singularity and a deviating argument x ″+ f (x) x′+ g (t, x (t− σ))= 0. When g has a strong …

In this paper, we study the existence, multiplicity and dynamics of positive periodic solutions
to a generalized Liénard equation with repulsive singularities. The Ambrosetti-Prodi type …

In this paper, we study the oscillation of a gas-filled spherical bubble immersed in an infinite
domain of incompressible liquid under the influence of a time-periodic acoustic field. The …

A periodic problem of Ambrosetti–Prodi type is studied in this paper for the Liénard equation
with a singularity of attractive type x ″+ f (x) x′+ φ (t) x m+ r (t) x μ= s, where f:(0,+∞)→ R is …

In this paper, we use the Leray–Schauder degree theory to study the following singular
periodic problems: x ″+ f (x′)+ g (t, x)= s, x (0)− x (T)= 0= x′(0)− x′(T), where f: ℝ→ ℝ is a …

The existence and multiplicity of T-periodic solutions to a class of differential equations with
attractive singularities at the origin are investigated in the paper. The approach is based on …

In this paper, we deal with the existence of positive periodic solutions of singular resonant
Duffing equations where g has a singularity at x= 0 and n is a positive integer. We give an …

We provide sufficient conditions for the existence and the asymptotic stability of periodic
positive solutions for a pipe/tank flow configuration. The model is a nonlinear ordinary …