The aim of this paper is to make an overview of some existence results for nonlinear differential and integral equations. Those results were obtained by the author and his co-workers during last years with some help of the technique of measures of noncompactness and a fixed point theorem of Darbo type.
Soit un compact polynomialement convexe de et son “potentiel logarithmique extrémal” dans . Supposons que est régulier (i.e. continue) et soit une fonction holomorphe sur un voisinage de . On construit alors une suite de polynôme de variables complexes avec deg pour , telle que l’erreur d’approximation soit contrôlée de façon assez précise en fonction du “pseudorayon de convergence” de par rapport à et du degré de convergence . Ce résultat est ensuite utilisé pour étendre...
Modification of behaviour in response to changes in the environment or ambient conditions, based on memory, is typical of the human and, possibly, many animal species.One obvious example of such adaptivity is, for instance, switching to a safer behaviour when in danger, from either a predator or an infectious disease. In human society such switching to safe behaviour is particularly apparent during epidemics. Mathematically, such changes of behaviour...
We develop several methods of realization of scalar product and generalized moment problems. Constructions are made by use of a Hilbertian method or a fixed point method. The constructed solutions are rational fractions and exponentials of polynomials. They are connected to entropy maximization. We give the general form of the maximizing solution. We show how it is deduced from the maximizing solution of the algebraic moment problem.