This paper addresses the issue of how to generate problem instances of controlled difficulty. It focuses on precedence- and resource-constrained (project) scheduling problems, but similar ideas may be applied to other network optimization problems. It describes a network construction procedure...

We consider a generalization of the classical resource constrained project scheduling problem. We introduce so-called partially renewable resources by assuming for each resource a capacity on subsets of periods. The concept of partially renewable resources is a fundamental tool in order to make,...