Stochastic finite element technique for stochastic one-dimensional time-dependent differential equations with random coefficients.
In some preceding works we consider a class of Boltz optimization problems for Lagrangian mechanical systems, where it is relevant a line , regarded as determined by its (variable) curvature function of domain . Assume that the problem is regular but has an impulsive monotone character in the sense that near each of some points to is monotone and is very large. In [10] we propose a procedure belonging to the theory of impulsive controls, in order to simplify into a structurally...
Soit une variété différentiable de dimension paire munie d’une 2-forme différentielle fermée générique . L’apparition éventuelle d’un lieu de dégénérescence du rang de est l’obstacle à ce que soit une structure symplectique. Nous étudions les propriétés géométriques de et nous caractérisons l’algèbre des hamiltoniennes admissibles de i.e. les fonctions différentiables qui possèdent un champ hamiltonien sur .
Starting from the considerations developed in [4], it is shown that the only forces at a distance exerted among the elements of an isolated spherical cluster of incoherent matter which, preserving homogeneity, is collapsing are those expressed by Newton's law of gravitation and those of the elastic type. Furthermore the reverse is shown, that is if the forces at a distance are of these two types during the collapse the homogeneity is preserved.
With reference to Nota I, the hypothesis that the cluster is spherical is substituted by the hypothesis that it has an isotropic behaviour with respect to a given frame of reference with origin in an element internal to . The kinematical behaviour of during the collapse with respect to the frames of reference with origin in the elements of and in translatory motion with respect to is studied. This behaviour is the same with respect to each of such frames, which are in translatory motion...
In the present paper we seek the bounce trajectories in a convex set which assume assigned positions in two fixed time instants. We find sufficient conditions in order to obtain the existence of infinitely many bounce trajectories.