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Continuation theorems for periodic perturbations of autonomous systems
It is first shown in this paper that, whenever it exists, the coincidence degree of the left-hand member of an autonomous differential equation x' - g(x) = 0, in the space of periodic functions with
Periodic Solutions of Liénard Equations with Asymmetric Nonlinearities at Resonance
The existence of $2\pi$ -periodic solutions of the second-order differential equation \[ x''+f(x)x'+ax^+-bx^-+g(x)=p(t), \qquad n\in \mathbb{N},\] where $a, b$ satisfy $1/\sqrt{a}+1/\sqrt{b}=2/n$ and
A Continuation Approach To Superlinear Periodic Boundary-value-problems
This paper deals with the problem of the existence of T-periodic solutions for the first order differential system x’ = I;( t, x), (1.1) where F: [0, T] x R” + R” is a Caratheodory function. In what
On the boundedness of solutions to a nonlinear singular oscillator
Abstract.We study a second order scalar equation of the form x′′ + V′(x) = p(t), where p is a π-perodic function and V is a singular potential. We give sufficient conditions on V, p ensuring that all
Cetaceans and tuna purse seine fisheries in the Atlantic and Indian Oceans: interactions but few mortalities
High survival rates suggest that setting nets close to cetaceans has a low immediate apparent impact on the species involved, and will contribute to the development of an ecosystem approach to managing fisheries and accurate cetACEan conservation measures.
Mortality of marine megafauna induced by fisheries: Insights from the whale shark, the world’s largest fish
The importance of estimating long-term post-release mortality rates by tracking individuals and/or by photographic identification to define precise conservation management measures is underline.
On the existence of two solutions with a prescribed number of zeros for a superlinear two-point boundary value problem
where the function f has superlinear growth at infinity and p grows at most linearly in u and u′. Our method is based on a continuation theorem for a coincidence equation of the form Lu = N(u, λ),
Infinitely many radial solutions to a boundary value problem in a ball
In this paper we are concerned with the existence and multiplicity of radial solutions to the BVP whereB is an open ball in ℝK and u↦∇·(a(|∇u|)∇u) is a nonlinear differential operator (e.g. the