Existence of Periodic Solutions of a Second-Order Singular Damped Differential Equation

Periodic solutions of fourth-order delay differential equation

In this paper the periodic solutions of fourth order delay differential equation of the form $ddddot{x}(t)+adddot{x}(t)+f(ddot{x}(t-tau(t)))+g(dot{x}(t-tau(t)))+h({x}(t-tau(t)))=p(t)$  is investigated. Some new positive periodic criteria are given.  

On Singular Solutions of a Second Order Differential Equation

In the paper, sufficient conditions are given under which all nontrivial solutions of (g(a(t)y))+r(t)f(y) = 0 are proper where a > 0, r > 0, f(x)x > 0, g(x)x > 0 for x 6= 0 and g is increasing on R. A sufficient condition for the existence of a singular solution of the second kind is given.

Recent Existence Results for Second-Order Singular Periodic Differential Equations

Twin Positive Periodic Solutions of Second Order Singular Differential Systems

In this paper, we study positive periodic solutions to singular second order differential systems. It is proved that such a problem has at least two positive periodic solutions. The proof relies on a nonlinear alternative of Leray–Schauder type and on Krasnosel’skĭı fixed point theorem on compression and expansion of cones.

Existence of Periodic Solutions for a Second Order Nonlinear Neutral Functional Differential Equation

We study the existence of periodic solutions of the second order nonlinear neutral differential equation with variable delay x′′ (t) + p (t)x′ (t) + q (t)h (x (t)) = c (t)x′ (t− τ (t)) + f (t, x (t− τ (t))) . We invert the given equation to obtain an integral, but equivalent, equation from which we define a fixed point mapping written as a sum of a large contraction and a compact map. We show t...