This is another model. Consider this particular schedule of the green job. We model this schedule as a vector. First we make the time discrete, and we put a 1 in correspondence with the times where the job is processed and 0 when it is not. So for instance in another case this could be another vector to indicate this kind of processing. If this another job with this vector for this processing we want to avoid that the two jobs overlap in time. Otherwise the machine would process both jobs at the same time.