  Experimental study of a uni junction transistor (UJT) has enabled to show
that this electronic component has the same features as the so-called
"memristor". So, we have used the memristor's direct current (DC) vM--iM
characteristic for modeling the UJT's DC current--voltage characteristic. This
has led us to confirm on the one hand, that the UJT is a memristor and, on the
other hand, to propose a new four-dimensional autonomous dynamical system
allowing to describe experimentally observed phenomena such as the transition
from a limit cycle to torus breakdown.
