What results from applying Lyapunov method for the linear systems with time-varying delay

It is noted, that the Lyapunov method appearing in the papers mentioned below in the section of References, applied to the linear systems with interval time-varying delay, may give very conservative stability conditions. The latter statement results from analyzing some benchmarks, used in these papers, for comparison of the obtained results. An insignificant enlargement of the stable delay interval, obtained in the successive paper, does not prevent from the fact, that the obtained stability condition is, as before, very conservative. Therefore some other reference point for estimation of the conservatism should be used. One of the simplest possibilities is the comparison with the stable delay interval for the same system with constant delay. An important role may play some appropriate simulations.