
Deborah Hendrych
I am interested in Mixed-Integer Non-Linear Optimization and first-order methods for solving non-linear, convex optimization problems. Currently, I am working on a Branch-and-Bound framework using Frank-Wolfe to solve the node problems.
Contact
- office
- Room 3106 at ZIB
- email shown with JavaScript enabled
- homepage
- www.deborahhendrych.com
- languages
- German and English
Curriculum vitae
- since 2023
- Member of BMS
- since 2023
- Researcher at ZIB
- May 2023
- M.Sc. in Mathematics at FUB
- 2021 to spring 2023
- Research Assistant at ZIB
- autumn 2020 to spring 2021
- Tutor at BHT
- Apr 2019
- B.Sc. in Mathematics at BHT
- autumn 2016 to spring 2018
- Tutor at BHT
Publications and preprints
Preprints and reports
- Sharma, K., Hendrych, D., Besançon, M., and Pokutta, S. (2024). Network Design for the Traffic Assignment Problem with Mixed-Integer Frank-Wolfe.
[arXiv]
[BibTeX]
@misc{2024_SharmaHendrychBesanconPokutta_NetworkdesignMicoFrankwolfe, archiveprefix = {arXiv}, eprint = {2402.00166}, arxiv = {arXiv:2402.00166}, primaryclass = {math.OC}, author = {Sharma, Kartikey and Hendrych, Deborah and Besançon, Mathieu and Pokutta, Sebastian}, title = {Network Design for the Traffic Assignment Problem with Mixed-Integer Frank-Wolfe}, date = {2024-01-31} } - Xiao, W., Hendrych, D., Besançon, M., and Pokutta, S. (2025). Boscia.jl: A review and tutorial.
[arXiv]
[BibTeX]
@misc{2025_XiaoHendrychBesanconPokutta_Bosciaminlp_2511-01479, archiveprefix = {arXiv}, eprint = {2511.01479}, arxiv = {arXiv:2511.01479}, primaryclass = {math.OC}, author = {Xiao, Wenjie and Hendrych, Deborah and Besançon, Mathieu and Pokutta, Sebastian}, title = {Boscia.jl: A review and tutorial}, date = {2025-11-03} } - Zimmer, M., Roux, C., Wagner, M., Hendrych, D., and Pokutta, S. (2025). SparseSwaps: Tractable LLM Pruning Mask Refinement at Scale.
[arXiv]
[BibTeX]
@misc{2025_ZimmerEtAl_Sparseswapspruning_2512-10922, archiveprefix = {arXiv}, eprint = {2512.10922}, arxiv = {arXiv:2512.10922}, primaryclass = {cs.LG}, author = {Zimmer, Max and Roux, Christophe and Wagner, Moritz and Hendrych, Deborah and Pokutta, Sebastian}, title = {SparseSwaps: Tractable LLM Pruning Mask Refinement at Scale}, date = {2025-12-11} } - Hendrych, D., Besançon, M., and Pokutta, S. (2026). Discrete eigenvalue optimization from entropic smoothing and first-order methods.
[arXiv]
[code]
[BibTeX]
@misc{2026_HendrychBesanconPokutta_DiscreteEigenvalueOptimization_2608-27024, archiveprefix = {arXiv}, eprint = {2608.27024}, arxiv = {arXiv:2608.27024}, primaryclass = {math.OC}, author = {Hendrych, Deborah and Besançon, Mathieu and Pokutta, Sebastian}, title = {Discrete eigenvalue optimization from entropic smoothing and first-order methods}, code = {https://github.com/ZIB-IOL/OptimalDesignWithBoscia}, date = {2026-08-27} }
Conference contributions
- Xiao, W., Besançon, M., Gelß, P., Hendrych, D., Klus, S., and Pokutta, S. (2026). Graph Isomorphism: Mixed-Integer Convex Optimization from First-Order Methods. Integration of Constraint Programming, Artificial Intelligence, and Operations Research, 16595, 614–630.
Associated with CPAIOR 2026.
DOI: 10.1007/978-3-032-27242-3_36
[arXiv]
[BibTeX]
@inproceedings{2025_XiaoEtAl_GraphisomorphismOptimization_2512-17417, year = {2026}, booktitle = {Integration of Constraint Programming, Artificial Intelligence, and Operations Research}, series = {Lecture Notes in Computer Science}, volume = {16595}, publisher = {Springer Science+Business Media}, pages = {614--630}, doi = {10.1007/978-3-032-27242-3_36}, archiveprefix = {arXiv}, eprint = {2512.17417}, arxiv = {arXiv:2512.17417}, primaryclass = {math.OC}, author = {Xiao, Wenjie and Besançon, Mathieu and Gelß, Patrick and Hendrych, Deborah and Klus, Stefan and Pokutta, Sebastian}, title = {Graph Isomorphism: Mixed-Integer Convex Optimization from First-Order Methods} } - Hendrych, D., Besançon, M., Martínez-Rubio, D., and Pokutta, S. (2025). Secant Line Search for Frank-Wolfe Algorithms. Proceedings of the 42nd International Conference on Machine Learning, 267.
Associated with ICML 2025.
[arXiv]
[BibTeX]
@inproceedings{2025_HendrychBesanconMartinezrubioPokutta_Secantfrankwolfe, year = {2025}, booktitle = {Proceedings of the 42nd International Conference on Machine Learning}, series = {Proceedings of Machine Learning Research}, volume = {267}, month = may, archiveprefix = {arXiv}, eprint = {2501.18775}, arxiv = {arXiv:2501.18775}, primaryclass = {math.OC}, author = {Hendrych, Deborah and Besançon, Mathieu and Martínez-Rubio, David and Pokutta, Sebastian}, title = {Secant Line Search for Frank-Wolfe Algorithms} } - Hendrych, D., Besançon, M., and Pokutta, S. (2024). Solving the Optimal Experiment Design Problem with Mixed-Integer Convex Methods. 22nd International Symposium on Experimental Algorithms (SEA 2024), 301, 16:1–16:22.
Associated with SEA 2024.
DOI: 10.4230/LIPIcs.SEA.2024.16
[arXiv]
[code]
[BibTeX]
@inproceedings{2023_HendrychBesanconPokutta_Optimalexperimentdesign, year = {2024}, booktitle = {22nd International Symposium on Experimental Algorithms (SEA 2024)}, series = {Leibniz International Proceedings in Informatics}, volume = {301}, publisher = {Schloss Dagstuhl – Leibniz Center for Informatics}, month = apr, pages = {16:1--16:22}, doi = {10.4230/LIPIcs.SEA.2024.16}, archiveprefix = {arXiv}, eprint = {2312.11200}, arxiv = {arXiv:2312.11200}, primaryclass = {math.OC}, author = {Hendrych, Deborah and Besançon, Mathieu and Pokutta, Sebastian}, title = {Solving the Optimal Experiment Design Problem with Mixed-Integer Convex Methods}, code = {https://github.com/ZIB-IOL/OptimalDesignWithBoscia} } - Sharma, K., Hendrych, D., Besançon, M., and Pokutta, S. (2024). Network Design for the Traffic Assignment Problem with Mixed-Integer Frank-Wolfe. Accepted at INFORMS Optimization Society Conference.
[arXiv]
[BibTeX]
@misc{2024_SharmaHendrychBesanconPokutta_NetworkdesignMicoFrankwolfe:1, howpublished = {Accepted at INFORMS Optimization Society Conference}, year = {2024}, archiveprefix = {arXiv}, eprint = {2402.00166}, arxiv = {arXiv:2402.00166}, primaryclass = {math.OC}, author = {Sharma, Kartikey and Hendrych, Deborah and Besançon, Mathieu and Pokutta, Sebastian}, title = {Network Design for the Traffic Assignment Problem with Mixed-Integer Frank-Wolfe} }
Articles, chapters and books
- Mexi, G., Hendrych, D., Designolle, S., Besançon, M., and Pokutta, S. (2026). A Frank-Wolfe-based primal heuristic for quadratic mixed-integer optimization. Mathematical Programming Computation.
DOI: 10.1007/s12532-026-00340-3
[URL]
[arXiv]
[code]
[BibTeX]
@article{2025_MexiEtAl_Frankwolfeheuristic_2508-01299, year = {2026}, date = {2026-09-03}, journal = {Mathematical Programming Computation}, month = sep, doi = {10.1007/s12532-026-00340-3}, url = {https://link.springer.com/article/10.1007/s12532-026-00340-3}, archiveprefix = {arXiv}, eprint = {2508.01299}, arxiv = {arXiv:2508.01299}, primaryclass = {math.OC}, author = {Mexi, Gioni and Hendrych, Deborah and Designolle, Sébastien and Besançon, Mathieu and Pokutta, Sebastian}, title = {A Frank-Wolfe-based primal heuristic for quadratic mixed-integer optimization}, code = {https://github.com/GioniMexi/FW-MIQCQP-Heuristic} } - Hendrych, D., Troppens, H., Besançon, M., and Pokutta, S. (2025). Convex mixed-integer optimization with Frank–Wolfe methods. Mathematical Programming Computation, 17(4), 731–757.
DOI: 10.1007/s12532-025-00288-w
[URL]
[arXiv]
[slides]
[code]
[BibTeX]
@article{2022_HendrychTroppensBesanconPokutta_Convexintegerfrankwolfe, year = {2025}, date = {2025-06-28}, journal = {Mathematical Programming Computation}, month = dec, volume = {17}, number = {4}, pages = {731--757}, doi = {10.1007/s12532-025-00288-w}, url = {https://link.springer.com/article/10.1007/s12532-025-00288-w}, archiveprefix = {arXiv}, eprint = {2208.11010}, arxiv = {arXiv:2208.11010}, primaryclass = {math.OC}, author = {Hendrych, Deborah and Troppens, Hannah and Besançon, Mathieu and Pokutta, Sebastian}, title = {Convex mixed-integer optimization with Frank–Wolfe methods}, code = {https://github.com/ZIB-IOL/Boscia.jl}, slides = {https://pokutta.com/slides/20220915_boscia.pdf} } - Besançon, M., Designolle, S., Halbey, J., Hendrych, D., Kuzinowicz, D., Pokutta, S., Troppens, H., Viladrich Herrmannsdoerfer, D., and Wirth, E. (2025). Improved Algorithms and Novel Applications of the FrankWolfe.jl Library. ACM Transactions on Mathematical Software, 51(4), 1–33.
DOI: 10.1145/3765626
[URL]
[arXiv]
[BibTeX]
@article{2025_BesanconEtAl_Frankwolfelibrary, year = {2025}, date = {2025-12-12}, journal = {ACM Transactions on Mathematical Software}, month = dec, volume = {51}, number = {4}, pages = {1--33}, doi = {10.1145/3765626}, url = {https://dl.acm.org/doi/10.1145/3765626}, archiveprefix = {arXiv}, eprint = {2501.14613}, arxiv = {arXiv:2501.14613}, primaryclass = {math.OC}, author = {Besançon, Mathieu and Designolle, Sébastien and Halbey, Jannis and Hendrych, Deborah and Kuzinowicz, Dominik and Pokutta, Sebastian and Troppens, Hannah and Viladrich Herrmannsdoerfer, Daniel and Wirth, Elias}, title = {Improved Algorithms and Novel Applications of the FrankWolfe.jl Library} }
Projects
This project develops oracle-based primal heuristic strategies for mixed-integer nonlinear programming (MINLP). Rather than relying on expensive interior-point solves, the approach leverages fast first-order oracles – Frank-Wolfe, conditional gradient, and proximal methods – to generate high-quality primal solutions within an MINLP branch-and-cut framework, targeting problems where traditional nonlinear solvers become prohibitively expensive.
This project investigates (mixed-)integer optimization with a non-convex, differentiable objective within a Branch-and-Bound framework utilizing Frank-Wolfe methods as node solvers. The focus is on incorporating spatial branching and comparing it to convexification strategies.
This project investigates mixed-integer optimization with convex objectives using error-adaptive convex solvers in branch-and-bound. The goal is to develop a faster branch-and-bound methodology by leveraging modern MILP techniques and error-adaptive methods, with key aspects including warm-starting and controlled inexactness in early termination.
Talks and posters
Conference and workshop talks
- Sep 2026
- Optimization Solvers and AI by Deborah Hendrych, Dominik Kamp and Gioni Mexi
IOL @ Speinshart Scientific Center for AI and SuperTech, Speinshart - Jun 2026
- Integer Frank-Wolfe for Optimal Experiment Design by Deborah Hendrych
SIAM conference on optimization (SIAMOP), Edinburgh - Jun 2026
- First-Order Convex (mixed-Integer) Optimization: FrankWolfe.jl and Boscia.jl by Deborah Hendrych
JuMP-dev Workshop (JuMP-dev), Edinburgh [PDF] [video] - Sep 2025
- Optimal Experiment Design with Mixed-Integer Convex Methods by Deborah Hendrych
16th Global Optimization Workshop (STOGO), Stockholm - Jul 2025
- Solving the Optimal Design Problem with Mixed-Integer Convex Methods by Deborah Hendrych
22nd Conference on Advances in Continuous Optimization (EUROPT), Southampton - Jul 2024
- Solving the Optimal Design Problem with Mixed-Integer Convex Methods by Deborah Hendrych
22nd Symposium on Experimental Algorithms (SEA), Vienna
Research seminar talks
- Jan 2026
- Solving the Optimal Design Problem with Mixed-Integer Convex Methods by Deborah Hendrych
Department of Mathematics, Singapore - Nov 2024
- Solving the Optimal Design Problem with Mixed-Integer Convex Methods by Deborah Hendrych
GHOST Research Seminar (GHOST), Grenoble - Jul 2024
- Solving the Optimal Design Problem with Mixed-Integer Convex Methods by Deborah Hendrych
NASPDE Seminar, Berlin - May 2024
- Solving the Optimal Design Problem with Mixed-Integer Convex Methods by Deborah Hendrych
MATH+ Spotlight talks, Berlin - Dec 2023
- Solving the Optimal Experiment Design Problems with Mixed-Integer Frank-Wolfe-Based Methods by Deborah Hendrych
IOL Research Seminar (IOL), Berlin
Poster presentations
- Jul 2026
- Recent Improvements on the Integer Frank-Wolfe Framework by Deborah Hendrych
ICOML Conference, Taipei - Jul 2026
- Recent Improvements on the Integer Frank-Wolfe Framework by Deborah Hendrych
8th DOxML Conference, Ookayama - Jul 2025
- Secant Line Search for Frank-Wolfe Algorithms by Deborah Hendrych
42nd International Conference on Machine Learning (ICML), Vancouver - May 2025
- Exploiting Combinatorial Algorithms Within Convex Mixed-Integer Optimization by Deborah Hendrych
7th DOxML Conference, Kyoto - Apr 2024
- Convex Solver Adaptivity for Mixed-Integer Optimization by Deborah Hendrych
5th Women in Optimization 2024 (WiO), Erlangen
Research Stays and Visits
- Jan 2026
- NUS hosted by Kim-Chuan Toh
- Oct 2024
- Universitè Grenoble Alpes hosted by Mathieu Besançon
- May 2025
- The Institute of Statistical Mathematics, Tokyo, Japan hosted by Bruno F. Lourenço
- Jul 2025
- Universitè Grenoble Alpes hosted by Mathieu Besançon
Events
- Sep 2026
- IOL @ Speinshart Scientific Center for AI and SuperTech, Speinshart
- Jul 2026
- ICOML Conference, Taipei
- Jul 2026
- 8th DOxML Conference, Ookayama
- Jun 2026
- SIAM conference on optimization (SIAMOP), Edinburgh
- May 2026
- JuMP-dev Workshop (JuMP-dev), Edinburgh
- Jan 2026
- 40th AAAI Conference on Artificial Intelligence (AAAI), Singapore
- Sep 2025
- 16th Global Optimization Workshop (STOGO), Stockholm
- Jul 2025
- 42nd International Conference on Machine Learning (ICML), Vancouver
- Jun 2025
- 22nd Conference on Advances in Continuous Optimization (EUROPT), Southampton
- May 2025
- 7th DOxML Conference, Kyoto
- Sep 2024
- 5th Computational Optimization at Work (CO@Work), Berlin
- Jul 2024
- 22nd Symposium on Experimental Algorithms (SEA), Vienna
- Apr 2024
- 5th Women in Optimization 2024 (WiO), Erlangen