No abstract

This paper presents four different control design strategies for linear quadratic regulators applied to DC-DC boost converters operating under large load range, pointing out advantages and drawbacks by means of a performance comparison. Two of the strategies are based on single controllers and the other two use a set of local controllers to cope with the entire load range. The robust stability of the closed-loop linearized system with the four control strategies is investigated via the existence of a common Lyapunov function, obtained in a fast and efficient way by the solution of linear matrix inequality conditions.

No abstract

The unidimensional Poisson-Boltzmann equation for a 1:2 (2:1) electrolyte has been solved analytically. The results have been compared with those obtained from the linearized equation. It is shown that in physiological conditions the difference may be greater than 10%. The value of the derivative of the potential in x=0, (dpsi/dx)x=0, has been used by many authors in the evaluation of the superficial charges of biological membranes. The value of (dpsi/dx)x-0 have also been compared with the ones derived from the linearized equation. The difference may be greater than 25%. Our results suggest that the linearization of the Poisson-Boltzmann equation for a 1:2(2:1) electrolyte may be greatly misleading.

No abstract