In this paper, a new condition for the controllability of higher order linear dynamical systems is obtained. The suggested test contains rank conditions of suitably defined matric...
Abstract. We establish the existence of positive solutions to twin time-scale problems given by the dynamic equation -u (t) = a(t)f(u(t)), t (t1, tn) T with boundary conditions u...
Abstract. The aim of this paper is to give sufficient conditions for a quasiconvex setvalued mapping to be convex. In particular, we recover several known characterizations of conv...
We consider an acoustic wave system with discontinuous coe cients and nonsmooth inputs. Existence, uniqueness and continuous dependence on input data of weak solutions are establi...