The thesis aims at elaborating a general model of design processes, applying it to database engineering and implementing it in the DB-MAIN CASE tool. It's a deterministic phenomenon which is managed by precise rules with no random element. In principal, the future is completely determined by the past. But, in practice, the uncertainty on initial conditions amplify in an exponential way and make long term prevision impossible. This is the property of sensitive dependence on initial conditions.
Strange attractors exist even in low dimensional systems.
This theses is concerned by the analysis of cardiac dynamics. There exists many abnormal cardiac rhythms which lead sometimes to death, especially the case of ventricular fibrillation. The cardiac rhythm result from the propagation of a wave in the 3-dimensional cardiac structure. This propagation allowed the contractions of the different parts of the cardiac muscle. From the measured signal and without the knowledge of any other state variable of the system, the attractor can be reconstructed in phase space.