A method is introduced to stabilize unstable discrete
systems, which does not require any adjustable control parameters of the
system. 2-dimension discrete Fold system and 3-dimension discrete hyperchaotic
system are stabilized to fixed points respectively. Numerical simulations are
then provided to show the effectiveness and feasibility of the proposed chaos
and hyperchaos controlling scheme.
Characteristic analysis of
transient electromagnetic disturbance data is very important. In this paper, the
time-domain and frequency-domain characteristics of transient electromagnetic
disturbance caused by switching operations in substations are analyzed. Two
methods are adopted in time-domain analysis. One method is histogram and the
other one is normality test. An appropriate procedure for the normality test is
proposed. Furthermore, the method used in frequency- domain analysis is to obtain
overall envelope. These statistical characteristic analysis methods are showed
to be of great value in analyses of the measured samples. The simulation
results showed that these methods are effective.