Scientific conferences have become an essential part of academic research and require significant investments (e.g. time and money) from their participants. It falls upon the organizers to develop a schedule that allows the participants to attend the talks of their interest. We present a...

We consider auctions of items that can be arranged in rows. Examples of such a setting appear in allocating pieces of land for real estate development, or seats in a theater or stadium. The objective is, given bids on subsets of items, to find a subset of bids that maximizes auction revenue...

Given a weighted graph G = (V, E), the Equitable Traveling Salesman Problem (ETSP) asks for two perfect matchings in G such that (1) the two matchings together form a Hamiltonian cycle in G and (2) the absolute difference in costs between the two matchings is minimized. The problem is shown to...

We investigate a problem inspired by the practical setting of scheduling a lock with parallel chambers. We show how this problem relates to known interval scheduling problems, as well as to a particular graph coloring problem on multiple unit interval graphs. We explore the relationships between...

We consider so-called balanced optimization problems with vector costs. We propose a framework containing such problems; this framework allows us to investigate the complexity and approximability of these problems in a general setting. More concrete, each problem in the framework admits a...

Inland waterways form a natural network infrastructure with capacity for more traffic. Transportation by ship is widely promoted as it is a reliable, efficient and environmental friendly way of transport. Nevertheless, locks managing the water level on waterways and within harbours sometimes...

In this note we study the complexity of the tool switching problem with non-uniform tool sizes. More speci cally, we consider the problem where the job sequence is given as part of the input. We show that the resulting tooling problem is strongly NP-complete, even in case of unit loading and...

Assembling printed circuit boards effciently using automated placement machines is a challenging task. Here, we focus on a motion control problem for a specific type of placement machines. More specifically,the problem is to establish movement patterns for the robot arm, the feeder rack,and...

Any sports league needs a schedule of play, and such a schedule can be important, as it may influence the outcome of the sports competition itself and since it may have an impact on the interests of all parties involved. As in many other sports leagues and countries, the interest for Belgian...

This paper focuses on revealed preference tests of the collective model of household consumption. We start by showing that the decision problems corresponding to testing collective rationality are NP-complete. This makes the application of these tests problematic for (increasingly available)...