On September 23, 2025, the seminar with Andrea Schaerf will take place.

A map to the location can be found on TU Maps.

Abstract

We consider a complex real-world problem in slab yard management that deals with block relocation and slab stack shuffling in a single problem. For this integrated problem, we designed a two-level metaheuristic approach with a local search procedure that works at the level of the slab selections and uses an inner greedy heuristic for deciding relocations and retrievals.

We tested our solution approach on a novel dataset using an actual yard layout and a simulation tool to set its initial configuration. Our search method successfully obtained high-quality solutions, even for large instances involving over 2000 slabs.

To assess the performance of our search method compared to state-of-the-art ones, we adapted it to a simpler formulation from recent literature and tested it on public benchmarks. Our method proved as good as the best existing ones in most available instances and consistently outperformed them on the largest ones.

About the Speaker

Andrea Schaerf received his PhD in Computer Science from University of Rome “La Sapienza” in 1994. From 1996 to 1998 he has been Assistant Professor at University of Rome “La Sapienza”. From 1998 to 2005 he has been Associate Professor at University of Udine, where, since 2005, he is Full Professor. From 2015 to 2021 he has been the Head of the School in Management Engineering. He has been Program Co-Chair of the following conferences: PATAT 2016, MIC 2011, and HM-2009. He is in the editorial board of ITOR and Journal of Scheduling. He has been Invited/Plenary Speaker at COMASA-2025, PATAT-2022, MESS-2018, and ORBEL 27. His main research interests are: Scheduling and Timetabling Problems, Local Search & Metaheuristics for Combinatorial Problems, and Problem Specification Languages and Tools.