Robust H∞ and Peak to Peak Output-feedback Control Analysis of the Glycolysis Pathway in Yeasts

The possible sensitivity and robustness of the Glycolysis pathway in yeasts is further explored via the H-infinity and the peak to peak L-infinity - L-infinity system norms, where the system encounters uncertainties in several kinetic parameters of its enzymes. Following linearization of the pathway kinetic equations, two modelling strategies are applied the first of which tests the robustness of the nominal linearized system to various parameter uncertainties, including uncertainties in the control gain matrix of the system. In the second strategy, similar tests of the latter are applied however, the original nonlinear system is modelled as an uncertain linear system where the extent of the nonlinearity is tuned by the uncertainty interval. It is shown that the system sensitivity to the various uncertain parameters agree in both strategies and that the two system performance indices, the H-infinity and the L-infinity-L-infinity reliably describe the system response to a concentration disturbance.