Former graduate student in the Daniel J. Epstein Department of Industrial and Systems Engineering Julien Yu (PhD ’24) has been awarded a Meritorious Paper Award from the INFORMS Journal on Computing. Yu is supervised by John Carlsson, the Kellner Family Early Career Chair and Associate Professor of Industrial and Systems Engineering.
The paper “A New Upper Bound for the Euclidean TSP Constant” focuses on the Beardwood-Halton-Hammersley (BHH) constant, β₂ — a fundamental mathematical constant discovered in 1959. The β₂ constant determines how the length of the traveling salesman tour of a set of points (the shortest tour that goes through a set of points) grows as the number of random points increases. The paper proves that β₂ is less than 0.9038, improving the upper bound by a significant amount for the first time since 1959.
Carlsson said the paper is notable in that it used a computer-aided proof approach that combined Monte Carlo simulation with decision trees, as opposed to a strictly analytical method. Yu and his co-authors generated millions of point configurations, determined optimal tours for each, and then used machine learning techniques to find regions where certain tour patterns consistently outperformed others.
Congratulations to Yu on this important recognition for his thesis.
Published on March 24th, 2025Last updated on April 11th, 2025