The total adjustment cost problem with variable activity durations and intensities

In this paper, we study the resource levelling problem with the so called total adjustment cost objective. For this problem, we propose a mixed-integer program in which, besides standard ingredients, variable durations and variable execution intensities of the activities are allowed to further smooth the shape of the resource profile function over time. To the best of our knowledge, there is no similar model for this problem with this objective function since the total adjustment cost problem is typically tacked within the literature with fixed activity durations and fixed execution intensities. A computational experimentation on known benchmarks has been conducted. Moreover, a comparison with a competing and highly performing model present in the literature for the same problem with fixed durations and fixed execution intensities of the activities is presented, properly adapting our model to work with the same setting.