Additionally, the influence of vapor boil-up on the structure of the optimal control pattern is observed, as well. In Figure , are plotted. Observations made, are as follows: the total number of cycles does not change for the decrease of the vapor boil-up to 2 [mol/h], but further "gradual/stepwise" decrease results in the "equal decrease" of the total number of cycles, since in the next step of the decrease by 4 [mol/h], the disappearance of the one cycle occurs; again up to 6