Managing and modelling generalresource transfersin (multi-)project scheduling

Most approaches to multi-project scheduling are based on the assumption that resources can betransferred between projects without any expense in time and cost. As this assumption often isnot realistic, we generalise the multi-project scheduling problem (RCMPSP) by additionallyincluding transfer times and cost. To integrate this aspect, in a first step, we develop a frameworkfor considering resource transfers in single and multi-project environments. It includesmanagerial approaches to handle resource transfers, a classification of resource transfer typesand new roles that resources can take in these transfers. Afterwards, we define the multi-projectscheduling problem with transfer times (RCMPSPTT) and formulate it in a basic and an extendedversion as integer linear programmes. Eventually, it is supplemented for the first time bycost considerations and introduced as resource constrained multi-project scheduling problemwith transfer times and cost (RCMPSPTTC). Computational experiments compare the presentedmanagerial approaches and prove the necessity of explicitly considering transfer times inproject scheduling. Moreover, the experiments evaluate the presented MIP models and showthat specialised solution procedures are vital...