Merlijn Staps wins Graduate School of Natural Sciences thesis award

On Wednesday 6 September, Merlijn Staps was awarded the Graduate School of Natural Sciences thesis award. He won the award for his thesis, “The diameter of hyperbolic random graphs”, the final project for his Master’s in Mathematical Sciences. Staps could not attend the award ceremony, since he is currently in the US for an internship at Princeton University. Therefore, Dean of the Faculty of Science Gerrit van Meer handed the award to Staps’ thesis supervisor, Tobias Muller. The other nominees for the award were Maarten Bransen (Nanomaterials Science), who also won this year's Utrecht University Master’s thesis award, and Abe Wits (Computing Science).

Staps studied the distances between points in networks, aiming to calculate the maximum distance between two points in ‘hyperbolic random graphs’. This is a difficult mathematical problem that several researchers had already attempted to solve. Staps was the first to find a solution to the problem, and will likely publish his results in an academic journal. The jury, consisting of Elwin Savelsbergh (Mathematics), Gerard Tel (Computer Science), Daan Wegener (Mathematics), Frank de Groot (Chemistry) and Carleen Tijm-Reijmer (Physics), praised Staps for the quality and depth of his work. They also commended him for opening his thesis with a layman’s introduction to the central concepts, making a thesis on such a complex topic clearly more accessible.

Maarten Bransen

Maarten Bransen combined physics and chemistry in his Master’s thesis, titled “Synthesis and Self-Assembly of Gold and Gold-Silver Nanorods”. He developed new chemical techniques to create extremely small particles in a controlled way and used highly sensitive 3D electron microscopy to analyse the particles he had created. The required techniques are very sensitive and a small mistake can ruin the entire outcome. Despite Bransen’s accurate and precise ways of working, quite a few attempts failed, as he describes in his thesis. However, Bransen kept going, documenting his experience to create better working procedures for future research. Both Bransen’s thesis supervisor and the jury were highly impressed by the quality of the thesis and the quantity of the experiments described.

Abe Wits

The thesis of Abe Wits (Computing Sciences is titled “Estimating Aggregations over Joins”. Wits researched and developed a method to calculate approximate answers to database queries that would involve a computationally intensive ‘join’ between two relational tables, without actually computing the join. Wits’ method gives much quicker answers, while keeping the error in the result under control and predictable. Wits checked his ideas in experiments with synthetic datasets, demonstrating that his method led to much better performance and smaller error compared to current practice. The jury very much enjoyed reading the thesis, which was written in a technical, but very clear style.

Photos: Ruud van Kooten