\input zb-basic \input zb-ioport \iteman{io-port 06004506} \itemau{Dai, Liming; Han, Lu} \itemti{Characteristics diagnosis of nonlinear dynamical systems.} \itemso{Luo, Albert C.J. (ed.) et al., Dynamical systems and methods. Based on the 3rd conference on nonlinear science and complexity (NSC), Ankara, Turkey, July 27--31, 2010. Berlin: Springer (ISBN 978-1-4614-0453-8/hbk; 978-1-4614-0454-5/ebook). 85-103 (2012).} \itemab The authors present contemporary methodologies used for diagnosis of characteristics of nonlinear dynamical systems behavior, they study their advantages in concrete situations and present a comparison. They consider a bifurcation approach, a fractal dimension approach, the usage of the spectrum of Lyaponov exponents and the periodicity ratio method at the usage of the Poincar\'{e} map. The example of the Duffing equation is used to investigate the behavior of nonlinear dynamical systems with the aid of Lyaponov exponent and periodicity ratio approaches. \itemrv{Boris V. Loginov (Ul'yanovsk)} \itemcc{} \itemut{nonlinear dynamic systems; diagnosis of characteristics} \itemli{doi:10.1007/978-1-4614-0454-5\_3} \end