The crew pairing problem (CPP) is generally modelled as a set partitioning problem where the flights have to be partitioned in pairings. A pairing is a sequence of flight legs separated by connection time and rest periods that starts and ends at the same base. Because of the extensive list of...

The line-planning problem seeks to determine the set of fixed routes (or lines) a transit operator should run, along with associated operation frequencies. We propose an optimization algorithm for the transit-line-planning problem based on bi-level programming that exploits the problem's...

A linear optimization problem which is amenable to column generation and contains a single parameter in the objective function is considered. We extend and adapt the standard linear programming column generation scheme to effectively and efficiently solve this problem for all values of the...

Evacuation drills are critical to evaluate emergency preparedness and infrastructure capacity. Before conducting drills, it is necessary to design the evacuation routes that people are likely to follow in a real evacuation. In this paper, we present a path-oriented optimization model for...

We consider a problem where customers dynamically request next-day home service, e.g., repair or instalment. Unlike attended home delivery, customers cannot select a time window (TW), but the service provider assigns a next-day TW to each new customer if the customer can feasibly be inserted in...