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Persistence and extinction of a stochastic delay predator-prey model under regime switching

Zhen Hai Liu, Qun Liu (2014)

Applications of Mathematics

The paper is concerned with a stochastic delay predator-prey model under regime switching. Sufficient conditions for extinction and non-persistence in the mean of the system are established. The threshold between persistence and extinction is also obtained for each population. Some numerical simulations are introduced to support our main results.

Perturbation singulière en dimension trois : canards en un point pseudo-singulier nœud

Éric Benoît (2001)

Bulletin de la Société Mathématique de France

On étudie les systèmes différentiels singulièrement perturbés de dimension 3 du type { x ˙ = f ( x , y , z , ε ) , y ˙ = g ( x , y , z , ε ) , ε z ˙ = h ( x , y , z , ε ) , f , g , h sont analytiques quelconques. Les travaux antérieurs étudiaient les points réguliers où la surface lente h = 0 est transverse au champ rapide vertical. C’est le domaine d’application du théorème de Tikhonov. Dans d’autres travaux antérieurs, on étudiait les singularités de certains types : plis et fronces de la surface lente, ainsi que certaines singularités plus compliquées, analogues aux points tournants...

Poincaré-Melnikov theory for n-dimensional diffeomorphisms

M. Baldomà, E. Fontich (1998)

Applicationes Mathematicae

We consider perturbations of n-dimensional maps having homo-heteroclinic connections of compact normally hyperbolic invariant manifolds. We justify the applicability of the Poincaré-Melnikov method by following a geometric approach. Several examples are included.

Polynomial algebra of constants of the Lotka-Volterra system

Jean Moulin Ollagnier, Andrzej Nowicki (1999)

Colloquium Mathematicae

Let k be a field of characteristic zero. We describe the kernel of any quadratic homogeneous derivation d:k[x,y,z] → k[x,y,z] of the form d = x ( C y + z ) x + y ( A z + x ) y + z ( B x + y ) z , called the Lotka-Volterra derivation, where A,B,C ∈ k.

Polynomial bounds for the oscillation of solutions of Fuchsian systems

Gal Binyamini, Sergei Yakovenko (2009)

Annales de l’institut Fourier

We study the problem of placing effective upper bounds for the number of zeroes of solutions of Fuchsian systems on the Riemann sphere. The principal result is an explicit (non-uniform) upper bound, polynomially growing on the frontier of the class of Fuchsian systems of a given dimension n having m singular points. As a function of n , m , this bound turns out to be double exponential in the precise sense explained in the paper.As a corollary, we obtain a solution of the so-called restricted infinitesimal...

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