Stability radii for positive linear time-invariant systems on time scales

We deal with dynamic equations on time scales, where we characterize the positivity of a system. Uniform exponential stability of a system is determined by the spectrum of its matrix. We investigate the corresponding stability radii with respect to structured perturbations and show that for positive systems the complex stability radius and the positive stability radius coincide. 2000 Mathematics Subject Classification. 15A48, 34D10, 39A11, 93D09