Time Dependency
When an activity must be carried out right after the preceding activity, these two activities are characterized as activities with time dependency. In highway projects, for example, prime coating activities should immediately follow the sweeping of the base course. Therefore, a time-dependent activity does not have the freedom to be performed at its own rate of production. Its rate of production is governed by the rate of production of its time dependent counterpart activity. In LOB calculations, time-dependent activities should be assigned the same rate of production in order not to provide an undesirable time gap between the two activities as the number of units increases @Fig. 3~a!#. The unified rate of production of time dependent activities can be decided by taking the production rate of whichever of the two activities is the dominant one. The other activity whose rate of production is adjusted will inevitably suffer idle times for its crews and/or equipment, since the adjusted rate of production will cease being a multiple of its natural rhythm @Fig. 3~b!#.