CRM Articles: Envíos recientes
Mostrando ítems 341-360 de 714
Numerical integration of high-order variational equations of ODEs
This paper discusses the numerical integration of high-order variational equations of ODEs. It is proved that, given a numerical method (say, any Runge–Kutta or Taylor method), to use automatic differentiation on this ...
Novel slow–fast behaviour in an oscillator driven by a frequency-switching force
When an oscillator switches abruptly between different frequencies, there is some ambiguity in deciding how the system should be modelled at the switch. Here we describe two seemingly natural models of a switch in a simple ...
Singular cotangent models in fluids with dissipation
In this article we analyze several mathematical models with singularities where the classical cotangent model is replaced by a b-cotangent model. We provide physical interpretations of the singular symplectic geometry ...
Breakdown of Heteroclinic Connections in the Analytic Hopf-Zero Singularity: Rigorous Computation of the Stokes Constant
Consider analytic generic unfoldings of the three- dimensional conservative Hopf-zero singularity. Under open conditions on the parameters determining the singularity, the unfolding possesses two saddle-foci when the ...
Characterization of land cover-specific fire regimes in the Brazilian Amazon
Humans profoundly alter fire regimes both directly, by introducing changes in fuel dynamics and ignitions, and indirectly, by increasing the release of greenhouse gases and aerosols from fires, which can alter regional ...
On the development of a consistent mathematical model for adsorption in a packed column (and why standard models fail)
In this paper we investigate the standard one-dimensional model for adsorption of a contaminant in a packed column. Initially we focus on two mass sink models: a full nonlinear Langmuir equation, including adsorption and ...
Phase-locking patterns underlying effective communication in exact firing rate models of neural networks
Macroscopic oscillations in the brain have been observed to be involved in many cognitive tasks but their role is not completely understood. One of the suggested functions of the oscillations is to dynamically modulate ...
Simultaneous Bifurcation of Limit Cycles and Critical Periods
The present work introduces the problem of simultaneous bifurcation of limit cycles and critical periods for a system of polynomial differential equations in the plane. The simultaneity concept is defined, as well as the ...
On the singular Weinstein conjecture and the existence of escape orbits for b-Beltrami fields
Motivated by Poincaré's orbits going to infinity in the (restricted) three-body problem [see H. Poincaré, Les Méthodes Nouvelles de la Mécanique Céleste, Vol. 3 (Gauthier-Villars, 1899) and A. Chenciner, Poincaré and the ...
Finite-size scaling of human-population distributions over fixed-size cells and its relation to fractal spatial structure
Using demographic data of high spatial resolution for a region in the south of Europe, we study the population over fixed-size spatial cells. We find that, counterintuitively, the distribution of the number of inhabitants ...
Modelling temperature-dependent dynamics of single and mixed infections in a plant virus
Multiple viral infection is an important issue in health and agriculture with strong impacts on society and the economy. Several investigations have dealt with the population dynamics of viruses with different dynamic ...
Finite-time scaling for epidemic processes with power-law superspreading events
Epidemics unfold by means of a spreading process from each infected individual to a variable number of secondary cases. It has been claimed that the so-called superspreading events of the COVID-19 pandemic are governed by ...
A Central Limit Theorem for inner functions
A Central Limit Theorem for linear combinations of iterates of an inner function is proved. The main technical tool is Aleksandrov Desintegration Theorem for Aleksandrov-Clark measures. © 2022 The Authors
Evoked and transmitted culture models: Using bayesian methods to infer the evolution of cultural traits in history
A central question in behavioral and social sciences is understanding to what extent cultural traits are inherited from previous generations, transmitted from adjacent populations or produced in response to changes in ...
Hodge–de Rham numbers of almost complex 4-manifolds
We introduce and study Hodge–de Rham numbers for compact almost complex 4-manifolds, generalizing the Hodge numbers of a complex surface. The main properties of these numbers in the case of complex surfaces are extended ...
The Santaló point for the Holmes-Thompson boundary area
We explore the notion of Santaló point for the Holmes-Thompson boundary area of a convex body in a normed space. In the case where the norm is C1, and in the case where unit ball and convex body coincide, we prove existence ...
Percolation on Random Graphs with a Fixed Degree Sequence
We consider bond percolation on random graphs with given degrees and bounded average degree. In particular, we consider the order of the largest component after the random deletion of the edges of such a random graph. We ...
On the cyclicity of Kolmogorov polycycles
In this paper we study planar polynomial Kolmogorov’s differential systems Xµ {ẋ = x f (x, y; µ), ẏ = yg(x, y; µ), with the parameter µ varying in an open subset Λ ⊂ RN. Compactifying Xµ to the Poincaré disc, the boundary ...
The local cyclicity problem: Melnikov method using Lyapunov constants
In 1991, Chicone and Jacobs showed the equivalence between the computation of the firstorder Taylor developments of the Lyapunov constants and the developments of the first Melnikov function near a non-degenerate monodromic ...
Environmental heterogeneity in human health studies. A compositional methodology for Land Use and Land cover data
The use of Land use and Land cover (LULC) data is gradually becoming more widely spread in studies relating the environment to human health. However, little research has acknowledged the compositional nature of these data. ...
