Scholar
Stephan Held
Google Scholar ID: HWEXkCEAAAAJ
Professor of Discrete Optimization at University of Bonn
Citations & Impact
Citations
346
H-index
9
i10-index
9
Publications
20
Co-authors
15
list available
Contact
Publications
Resume (English only)
Academic Achievements
- Published 'Vehicle Routing with Time-Dependent Travel Times: Theory, Practice, and Benchmarks' in Discrete Optimization (2024)
- Published 'Local Search with Learned Constraints for Last Mile Routing' in Transportation Science (2024), detailing the winning approach of the 2021 Amazon challenge
- Multiple papers accepted at top venues including DAC 2025, ALENEX 2026, and APPROX/RANDOM 2023
- Released open-source code and benchmark datasets for graph coloring and vehicle routing
- Advanced approximation algorithms for the uniform cost-distance Steiner tree problem
Research Experience
- Works on VLSI design topics including clock scheduling, gate sizing, repeater trees, threshold voltage optimization, logic resynthesis, and timing-driven placement & routing
- Developed exactcolors, one of the fastest open-source solvers for maximum-weight stable set and graph coloring
- Co-developed the TSP solver 'Just Passing Through' with William Cook and Keld Helsgaun, winning the 2021 Amazon-MIT Last Mile Routing Challenge
- Collaborates with Greenplan on combinatorial optimization for real-world pickup and delivery services
- Created realistic vehicle routing instances with time-dependent travel times using OpenStreetMap and Uber speed profiles
Background
- Professor at the Research Institute for Discrete Mathematics, University of Bonn, Germany
- Research interests include VLSI design, graph coloring, and vehicle routing
- Collaborates with industry partners such as IBM and Greenplan
- Associate editor of the journal Discrete Optimization
- General Chair of the International Symposium on Physical Design (ISPD) 2026
