Many systems used in practice include
various sources of energy dissipation (nodes with
external and internal friction, ferromagnets, ferroelectric
capacitors, and others), switching devices and nonlinear
elements with an ambiguous static characteristic. For such
systems, called hysteresis systems, with an arbitrary law of
variation of the input coordinate X(t) , the motion of the
representing point will have a complex hysteresis nature,
when a finite or infinite set of values of the output coordinate
Y corresponds to one value of X.
Hysteresis systems are called static systems in the range
|X|<X0, where X0 is a certain threshold value of speed, at
exceeding which the speed affects the course of the hysteresis
curves, if the shape and slope of the branches of the hysteresis
loops do not depend on the value in the indicated range
of speeds; at that, at the turning points at which the sign
changes to the opposite sign, an acute-angled shape of the
loop (tips) with a break of the first kind is observed.

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