A Comparative Performance Analysis of Two MILP Formulations for the Resource-Renting-Problem

In this paper, we consider the RRP/max, an ex-tension of the well-known resource availability problem (RAP). The RRP/max does not only consider procurement costs but also time-dependent renting costs for resources used in a project. The objective of the RRP/max is to determine time-feasible starting times for all activities while minimizing the total resource cost to execute a project with general temporal constraints. We present two time-indexed MILP formulations as well as some new restrictions for the domains of the variables. To compare the presented models, we devised an extensive computational study where we compare the performance of the two formulations for benchmark instances from the literature.