A major aim of the Research Campus MODAL is the development and use of mathematical synergies between the individual labs of the network. In this context, the fields of...
Natural gas is one of the most important energy sources in Germany and Europe. In recent years, political regulations have led to a strict separation of gas trading and...
Symmetries arise naturally in integer programs. Often, there is no reason to distinguish certain objects among others. For instance, the actual number that a certain bus...
A Context-Aware Cutting Plane Selection Algorithm for Mixed-Integer Programming
Operation Research Proceedings, 2023 (accepted for publication, preprint available as ZIB-Report 23-21)
Mark Turner, Timo Berthold, Mathieu BesançonPDF (ZIB-Report) BibTeX
Cutting Plane Selection with Analytic Centers and Multiregression
Integration of Constraint Programming, Artificial Intelligence, and Operations Research. CPAIOR 2023., pp. 52-68, Vol.13884, Lecture Notes in Computer Science, 2023 (preprint available as ZIB-Report 22-28)
Mark Turner, Timo Berthold, Mathieu Besançon, Thorsten KochPDF (ZIB-Report) BibTeX DOI
Improving Conflict Analysis in MIP Solvers by Pseudo-Boolean Reasoning
29th International Conference on Principles and Practice of Constraint Programming (CP 2023), pp. 27:1-27:19, Vol.280, Leibniz International Proceedings in Informatics (LIPIcs), 2023
Gioni Mexi, Timo Berthold, Ambros Gleixner, Jakob Nordström
BibTeX DOI
Using Multiple Reference Vectors and Objective Scaling in the Feasibility Pump
EURO Journal on Computational Optimization, Vol.11, 2023 (preprint available as ZIB-Report 22-14)
Timo Berthold, Gioni Mexi, Domenico Salvagnin
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MILP. Try. Repeat.
Proceedings of the 13th International Conference on the Practice and Theory of Automated Timetabling - PATAT 2021, Vol.2, 2021
Timo Berthold, Thorsten Koch, Yuji ShinanoBibTeX
An exploratory computational analysis of dual degeneracy in mixed-integer programming
EURO Journal on Computational Optimization, pp. 241-246, 2020
Gerald Gamrath, Timo Berthold, Domenico Salvagnin
BibTeX DOI
Conflict-Free Learning for Mixed Integer Programming
Integration of AI and OR Techniques in Constraint Programming. CPAIOR 2020, pp. 521-530, LNCS, 2020 (preprint available as ZIB-Report 19-59)
Jakob Witzig, Timo BertholdPDF (ZIB-Report) BibTeX DOI
The confined primal integral: a measure to benchmark heuristic MINLP solvers against global MINLP solvers
Mathematical Programming, 2020
Zsolt Csizmadia, Timo BertholdBibTeX DOI
A Status Report on Conflict Analysis in Mixed Integer Nonlinear Programming
Integration of AI and OR Techniques in Constraint Programming. CPAIOR 2019, pp. 84-94, Vol.11494, LNCS, 2019 (preprint available as ZIB-Report 18-57)
Jakob Witzig, Timo Berthold, Stefan HeinzPDF (ZIB-Report) BibTeX DOI
Local Rapid Learning for Integer Programs
Integration of AI and OR Techniques in Constraint Programming. CPAIOR 2019, pp. 67-83, Vol.11494, LNCS, 2019 (preprint available as ZIB-Report 18-56)
Timo Berthold, Peter Stuckey, Jakob WitzigPDF (ZIB-Report) BibTeX DOI
Strategic Planning of Rolling Stock Rotations for Public Tenders
Proceedings of the 8th International Conference on Railway Operations Modelling and Analysis - RailNorrköping 2019, pp. 148-159, Linköping Electronic Conference Proceedings(069), 2019, ISBN: 978-91-7929-992-7
Timo Berthold, Boris Grimm, Markus Reuther, Stanley Schade, Thomas SchlechtePDF BibTeX
Four Good Reasons to Use an Interior Point Solver Within a MIP Solver
Kliewer N., Ehmke J., Borndörfer R. (eds) Operations Research Proceedings 2017, pp. 159-164, 2018 (preprint available as ZIB-Report 17-42)
Timo Berthold, Michael Perregaard, Csaba Mészáros
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ParaXpress: An Experimental Extension of the FICO Xpress-Optimizer to Solve Hard MIPs on Supercomputers
Optimization Methods & Software, 33(3), pp. 530-539, 2018
Yuji Shinano, Timo Berthold, Stefan HeinzBibTeX DOI
Parallel Solvers for Mixed Integer Linear Optimization
Handbook of Parallel Constraint Reasoning, pp. 283-336, Youssef Hamadi (Ed.), Springer Nature, 2018 (preprint available as ZIB-Report 16-74)
Ted Ralphs, Yuji Shinano, Timo Berthold, Thorsten KochPDF (ZIB-Report) BibTeX DOI
Parallelization of the FICO Xpress Optimizer
Optimization Methods and Software, 33(3), pp. 518-529, 2018
Timo Berthold, James Farmer, Stefan Heinz, Michael Perregaard
BibTeX DOI
From feasibility to improvement to proof: three phases of solving mixed-integer programs
Optimization Methods and Software, 33(3), pp. 499-517, 2017 (preprint available as ZIB-Report 16-78)
Timo Berthold, Gregor Hendel, Thorsten KochPDF (ZIB-Report) BibTeX DOI
A First Implementation of ParaXpress: Combining Internal and External Parallelization to Solve MIPs on Supercomputers
Mathematical Software - ICMS 2016, 5th International Conference Berlin, Germany, July 11-14, 2016 Proceedings, pp. 308-316, 2016
Yuji Shinano, Timo Berthold, Stefan HeinzBibTeX DOI
Parallelization of the FICO Xpress-Optimizer
Mathematical Software - ICMS 2016, 5th International Conference Berlin, Germany, July 11-14, 2016 Proceedings, pp. 251-258, 2016
Timo Berthold, James Farmer, Stefan Heinz, Michael Perregaard
BibTeX DOI
Branching on Multi-aggregated Variables
Integration of AI and OR Techniques in Constraint Programming. CPAIOR 2015, pp. 141-156, Vol.9075, Lecture Notes in Computer Science, 2015 (preprint available as ZIB-Report 15-10)
Gerald Gamrath, Anna Melchiori, Timo Berthold, Ambros Gleixner, Domenico Salvagnin
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A Jack of all Trades? Solving stochastic mixed-integer nonlinear constraint programs
MATHEON - Mathematics for Key Technologies, Vol.1, pp. 135-146, Peter Deuflhard, Martin Grötschel, Dietmar Hömberg, Ulrich Horst, Jürg Kramer, Volker Mehrmann, Konrad Polthier, Frank Schmidt, Christof Schütte, Martin Skutella, Jürgen Sprekels (Eds.), European Mathematical Society, 2014 (preprint available as )
Thomas Arnold, Timo Berthold, Stefan Heinz, Stefan Vigerske, René Henrion, Martin Grötschel, Thorsten Koch, Caren Tischendorf, Werner Römisch
BibTeX DOI
Heuristic algorithms in global MINLP solvers
Doctoral thesis, Technische Universität Berlin, Martin Grötschel, Thorsten Koch, Andrea Lodi (Advisors), 2014, ISBN: 978-3-8439-1931-9
Timo BertholdBibTeX
Cloud branching
Integration of AI and OR Techniques in Constraint Programming for Combinatorial Optimization Problems, Vol.7874, pp. 28-43, Carla Gomes, Meinolf Sellmann (Eds.), Springer, 2013 (preprint available as ZIB-Report 13-01)
Timo Berthold, Domenico Salvagnin
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Measuring the impact of primal heuristics
Operations Research Letters, 41(6), pp. 611-614, 2013 (preprint available as ZIB-Report 13-17)
Timo BertholdPDF (ZIB-Report) BibTeX DOI
Undercover Branching
Experimental Algorithms, 12th International Symposium, SEA 2013, Rome, Italy, June 5-7, 2013, Proceedings, Vincenzo Bonifaci, Camil Demetrescu, Alberto Marchetti-Spaccamela (Eds.), pp. 212-223, Vol.7933, Lecture Notes in Computer Science, 2013 (preprint available as ZIB-Report 13-14)
Timo Berthold, Ambros GleixnerPDF (ZIB-Report) BibTeX DOI
An approximative Criterion for the Potential of Energetic Reasoning
Theory and Practice of Algorithms in (Computer) Systems, pp. 229-239, Vol.6595, Lecture Notes in Computer Science, 2011 (preprint available as ZIB-Report 11-12)
Timo Berthold, Stefan Heinz, Jens Schulz
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Large Neighborhood Search beyond MIP
Proceedings of the 9th Metaheuristics International Conference (MIC 2011), pp. 51-60, 2011, ISBN: 978-88-900984-3-7 (preprint available as ZIB-Report 11-21)
Timo Berthold, Stefan Heinz, Marc Pfetsch, Stefan VigerskePDF (ZIB-Report) BibTeX
A Constraint Integer Programming Approach for Resource-Constrained Project Scheduling
Proc. of CPAIOR 2010, Andrea Lodi, Michela Milano, Paolo Toth (Eds.), pp. 313-317, Vol.6140, LNCS, 2010 (preprint available as ZIB-Report 10-03)
Timo Berthold, Stefan Heinz, Marco Lübbecke, Rolf Möhring, Jens Schulz
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Rapid Learning for Binary Programs
Proc. of CPAIOR 2010, Andrea Lodi, Michela Milano, Paolo Toth (Eds.), pp. 51-55, Vol.6140, LNCS, 2010 (preprint available as ZIB-Report 10-04)
Timo Berthold, Thibaut Feydy, Peter Stuckey
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Undercover – a primal heuristic for MINLP based on sub-MIPs generated by set covering
Proceedings of the European Workshop on Mixed Integer Nonlinear Programming, April 12-16, 2010, Marseilles, France, Pierre Bonami, Leo Liberti, Andrew J. Miller, Annick Sartenaer (Eds.), pp. 103-112, 2010 (preprint available as ZIB-Report 09-40)
Timo Berthold, Ambros GleixnerPDF (ZIB-Report) PDF (ZIB-Report) PDF (ZIB-Report) BibTeX
Detecting Orbitopal Symmetries
Operations Research Proceedings 2008, Bernhard Fleischmann, Karl Borgwardt, Robert Klein, Axel Tuma (Eds.), pp. 433-438, 2009 (preprint available as ZIB-Report 08-33)
Timo Berthold, Marc Pfetsch
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Hybrid Branching
Integration of AI and OR Techniques in Constraint Programming for Combinatorial Optimization Problems, 6th International Conference, CPAIOR 2009, Willem van Hoeve, John Hooker (Eds.), pp. 309-311, Vol.5547, Lecture Notes in Computer Science, 2009
Tobias Achterberg, Timo BertholdBibTeX
Nonlinear pseudo-Boolean optimization
Theory and Applications of Satisfiability Testing – SAT 2009, Oliver Kullmann (Ed.), pp. 441-446, Vol.5584, Lecture Notes in Computer Science, 2009 (preprint available as ZIB-Report 09-11)
Timo Berthold, Stefan Heinz, Marc Pfetsch
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Constraint Integer Programming: A New Approach to Integrate CP and MIP
Integration of AI and OR Techniques in Constraint Programming for Combinatorial Optimization Problems, 5th International Conference, CPAIOR 2008, Laurent Perron, Michael Trick (Eds.), pp. 6-20, Vol.5015, Lecture Notes in Computer Science, 2008 (preprint available as ZIB-Report 08-01)
Tobias Achterberg, Timo Berthold, Thorsten Koch, Kati Wolter
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Heuristics of the Branch-Cut-and-Price-Framework SCIP
Operations Research Proceedings 2007, Jörg Kalcsics, Stefan Nickel (Eds.), pp. 31-36, 2008 (preprint available as ZIB-Report 07-30)
Timo BertholdPDF (ZIB-Report) BibTeX
Primal Heuristics for Mixed Integer Programs
Master's thesis, Technische Universität Berlin, 2006 (preprint available as )
Timo BertholdPDF (ZIB-Report) BibTeX