Oscillations de systèmes hamiltoniens non linéaires. III
Oscillations presque-périodiques forcées d'équations d'Euler-Lagrange
Pattern Formation of Competing Microorganisms in Sediments
We present a three species model describing the degradation of substrate by two competing populations of microorganisms in a marine sediment. Considering diffusion to be the main transport process, we obtain a reaction diffusion system (RDS) which we study in terms of spontaneous pattern formation. We find that the conditions for patterns to evolve are likely to be fulfilled in the sediment. Additionally, we present simulations that are consistent with experimental data from the literature. We...
Periodic orbits close to elliptic tori and applications to the three-body problem
We prove, under suitable non-resonance and non-degeneracy “twist” conditions, a Birkhoff-Lewis type result showing the existence of infinitely many periodic solutions, with larger and larger minimal period, accumulating onto elliptic invariant tori (of hamiltonian systems). We prove the applicability of this result to the spatial planetary three-body problem in the small eccentricity-inclination regime. Furthermore, we find other periodic orbits under some restrictions on the period and the masses...
Periodic points and chaotic-like dynamics of planar maps associated to nonlinear Hill's equations with indefinite weight.
Possibly Longest Food Chain: Analysis of a Mathematical Model
We consider the number of trophic levels in a food chain given by the equilibrium state for a simple mathematical model with ordinary differential equations which govern the temporal variation of the energy reserve in each trophic level. When a new trophic level invades over the top of the chain, the chain could lengthen by one trophic level. We can derive the condition that such lengthening could occur, and prove that the possibly longest chain is globally stable. In some specific cases,...
Problème général de la stabilité du mouvement
Pružné kyvadlo pohledem teorie dynamických systémů
Pseudo-abelian integrals on slow-fast Darboux systems
We study pseudo-abelian integrals associated with polynomial deformations of slow-fast Darboux integrable systems. Under some assumptions we prove local boundedness of the number of their zeros.
Quadratic systems with homoclinic cycles described by quintic curves.
Quelques propriétés des lignes critiques d'une récurrence du second ordre à inverse non unique. Détermination d'une zone absorbante
Regular and chaotic motion of a bush-shaft system with tribological processes.
Resonance surfaces for forced oscillators.
Resonance with respect to the Fučík spectrum.
Response of a class of mechanical oscillators described by a novel system of differential-algebraic equations
We study the vibration of lumped parameter systems whose constituents are described through novel constitutive relations, namely implicit relations between the forces acting on the system and appropriate kinematical variables such as the displacement and velocity of the constituent. In the classical approach constitutive expressions are provided for the force in terms of appropriate kinematical variables, which when substituted into the balance of linear momentum leads to a single governing ordinary...
Rigorous numerical stability estimates for the existence of KAM tori in a forced pendulum
Seventy-five years of global analysis around the forced pendulum equation
Small divisors and large multipliers
We study germs of singular holomorphic vector fields at the origin of of which the linear part is -resonant and which have a polynomial normal form. The formal normalizing diffeomorphism is usually divergent at the origin but there exists holomorphic diffeomorphisms in some “sectorial domains” which transform these vector fields into their normal form. In this article, we study the interplay between the small divisors phenomenon and the Gevrey character of the sectorial normalizing diffeomorphisms....
Solutions to Lyapunov stability problems: Nonlinear systems with continuous motions.
Special issue: Nonlinear dynamics and their applications to engineering sciences. Selected papers based on the presentations at the conference on nonlinear dynamics (ND-KPI 2004), Kharkow, Ukraine, September 14--16, 2004.