Szukana fraza: [Abstract = "The paper is devoted to the problem of observability and controllability analysis in nonlinear dynamic systems. Both continuous\- and discrete\-time systems described by nonlinear differential or difference equations, respectively, are onsidered. A new approach is developed to solve this problem whose features include \(i\) consideration of systems with non\-differentiable nonlinearities and \(ii\) the use of relatively simple linear methods which may be supported by existing programming systems, e.g.,Matlab"]