Özet:
Methods for algebraically determining the signs and the magnitudes of Lyapunov exponents of a given dynamical system are studied.A number of Hamiltonian and dissipative systems are investigated.The existence of zero Lyapunov exponents for the Toda and Henon-Heiles systems are shown using the curvature of their potentials functions.For the Rossler system,the root bracketing criterion is used to show the existence of a zero Lyapunov exponent.The approximate Lyapunov spectra of Lorenz and Rossler systems are computed using the approximation schemes introduced.