ASYMPTOTIC STABILITY FOR TIME-VARIANT SYSTEMS AND OBSERVABILITY - UNIFORM AND NONUNIFORM CRITERIA

This paper presents some new criteria for uniform and nonuniform asymp totic stability of equilibria for time-variant differential equations and this within a Lyapunov approach. The stability criteria are formul ated in terms of certain observability conditions with the output deri ved from the Lyapunov function. For some classes of systems, this syst em theoretic interpretation proves to be fruitful since-after establis hing the invariance of observability under output injection-this enabl es us to check the stability criteria on a simpler system. This proced ure is illustrated for some classical examples.