which bus i is held at the stop associated with event k, while Sui(k) is a binary variable that is equal to one if passengers at allowed to board bus i at the stop associated with event k, zero otherwise.
The output variables correspond to the estimated passenger load ^L ðk þ 1Þ and the estimated departure time T^d ðk þ 1Þ
i i
once the bus departs from its current stop, associated with the bus i that triggered event k.