People - Mathematical Algorithmic Optimization

2023

article

Hahn, M., Leyffer, S., Sager, S.

Binary Optimal Control by Trust-Region Steepest Descent

Mathematical Programming

BibTeX

DOI

@article{Hahn2023,
    author = {Hahn, Mirko and Leyffer, Sven and Sager, Sebastian},
    title = {Binary Optimal Control by Trust-Region Steepest Descent},
    journal = {Mathematical Programming},
    year = {2023},
    volume = {197},
    number = {1},
    pages = {147--190},
    doi = {10.1007/s10107-021-01733-z}
}

2023

article

Manns, P., Hahn, M., Kirches, C., Leyffer, S., Sager, S.

On convergence of binary trust-region steepest descent

Journal of Nonsmooth Analysis and Optimization

BibTeX

DOI

@article{Manns2023,
    author = {Manns, Paul and Hahn, Mirko and Kirches, Christian and Leyffer, Sven and Sager, Sebastian},
    title = {On convergence of binary trust-region steepest descent},
    journal = {Journal of Nonsmooth Analysis and Optimization},
    publisher = {Episciences. org},
    year = {2023},
    volume = {4},
    pages = {10164},
    doi = {10.46298/jnsao-2023-10164}
}

2022

incollection

Hahn, M., Kirches, C., Manns, P., Sager, S., Zeile, C.

Decomposition and approximation for PDE-constrained mixed-integer optimal control

SPP1962 Special Issue Non-Smooth and Complementarity-Based Distributed Parameter Systems

BibTeX

Web

@incollection{Hahn2022a,
    author = {Hahn, M. and Kirches, C. and Manns, P. and Sager, S. and Zeile, C.},
    title = {Decomposition and approximation for PDE-constrained mixed-integer optimal control},
    booktitle = {SPP1962 Special Issue Non-Smooth and Complementarity-Based Distributed Parameter Systems},
    publisher = {Birkh\"{a}user},
    year = {2022},
    editor = {Hinterm\"{u}ller, M. et al.},
    pages = {283--306},
    url = {https://mathopt.de/publications/Hahn2019.pdf}
}

2022

article

Le, D., Merkert, M., Sorgatz, S., Hahn, M., Sager, S.

Autonomous traffic at intersections: an optimization-based analysis of possible time, energy, and CO2 savings

Networks

BibTeX

DOI Web

@article{Le2022,
    author = {Le, D.D. and Merkert, M. and Sorgatz, S. and Hahn, M. and Sager, S.},
    title = {Autonomous traffic at intersections: an optimization-based analysis of possible time, energy, and {CO2} savings},
    journal = {Networks},
    year = {2022},
    volume = {79},
    number = {3},
    pages = {338--363},
    url = {https://optimization-online.org/?p=16226},
    doi = {10.1002/net.22078}
}

2020

inproceedings

Bürger, A., Zeile, C., Hahn, M., Altmann-Dieses, A., Sager, S., Diehl, M.

pycombina: An Open-Source Tool for Solving Combinatorial Approximation Problems arising in Mixed-Integer Optimal Control

IFAC

BibTeX

DOI

@inproceedings{Buerger2020,
    author = {B\"urger, A. and Zeile, C. and Hahn, M. and Altmann-Dieses, A. and Sager, S. and Diehl, M.},
    title = {pycombina: An Open-Source Tool for Solving Combinatorial Approximation Problems arising in Mixed-Integer Optimal Control},
    journal = {IFAC},
    year = {2020},
    volume = {53},
    pages = {6502--6508},
    doi = {10.1016/j.ifacol.2020.12.1799}
}

2020

incollection

Garmatter, D., Maggi, A., Wenzel, M., Monem, S., Hahn, M., Stoll, M., Sager, S., Benner, P., Sundmacher, K.

Power-to-Chemicals: A Superstructure Problem for Sustainable Syngas Production

Mathematical Modeling, Simulation and Optimization for Power Engineering and Management

BibTeX

@incollection{Garmatter2020,
    author = {Garmatter, D. and Maggi, A. and Wenzel, M. and Monem, S. and Hahn, M. and Stoll, M. and Sager, S. and Benner, P. and Sundmacher, K.},
    title = {Power-to-Chemicals: A Superstructure Problem for Sustainable Syngas Production},
    booktitle = {Mathematical Modeling, Simulation and Optimization for Power Engineering and Management},
    publisher = {Springer},
    year = {2020},
    pages = {145--168}
}

2020

article

Sharma, M., Hahn, M., Leyffer, S., Ruthotto, L., van Bloemen Waanders, B.

Inversion of Convection-Diffusion Equation with Discrete Sources

Optimization and Engineering

Abstract BibTeX

DOI

We present a convection-diffusion inverse problem that aims to identify an unknown number of sources and their locations. We model the sources using a binary function, and we show that the inverse problem can be formulated as a large-scale mixed-integer nonlinear optimization problem. We show empirically that current state-of-the-art mixed-integer solvers cannot solve this problem and that applying simple rounding heuristics to solutions of the relaxed problem can fail to identify the correct number and location of the sources. We develop two new rounding heuristics that exploit the value and a physical interpretation of the continuous relaxation solution, and we apply a steepest-descent improvement heuristic to obtain satisfactory solutions to both two- and three-dimensional inverse problems. We also provide the code used in our numerical experiments in open-source format.

@article{Sharma2019,
    author = {Sharma, M. and Hahn, M. and Leyffer, S. and Ruthotto, L. and van Bloemen Waanders, B.},
    title = {Inversion of Convection-Diffusion Equation with Discrete Sources},
    journal = {Optimization and Engineering},
    year = {2020},
    doi = {10.1007/s11081-020-09536-5}
}

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