Applied and Computational Mathematics (ACM)

Model Order Reduction

Model Order Reduction (MOR) is the art of reducing a system's complexity while preserving its input-output behavior as much as possible.

Processes in all fields of todays technological world, like physics, chemistry and electronics, but also in finance, are very often described by dynamical systems. With the help of these dynamical systems, computer simulations, i.e. virtual experiments, are carried out. In this way, new products can be designed without having to build costly prototyps.

Due to the demand of more and more realistic simulations, the dynamical systems, i.e., the mathematical models, have to reflect more and more details of the real world problem. By this, the models' dimensions are increasing and simulations can often be carried out at high computational cost only.

In the design process, however, results are needed quickly. In circuit design, e.g., structures may need to be changed or parameters may need to be altered, in order to satisfy design rules or meet the prescribed performance. One cannot afford idle time, waiting for long simulation runs to be ready.

Model Order Reduction allows to speed up simulations in cases where one is not interested in all details of a system but merely in its input-output behavior. That means, considering a system, one may ask:

  • How do varying parameters influence certain performances ?
    Using the example of circuit design: How do widths and lengths of transistor channels, e.g., influence the voltage gain of a circuit.
  • Is a system stable?
    Using the example of circuit design: In which frequency range, e.g., of voltage sources, does the circuit perform as expected
  • How do coupled subproblems interact?
    Using the example of circuit design: How are signals applied at input-terminals translated to output-pins?

Classical situations in circuit design, where one does not need to know internals of blocks are optimization of design parameters (widths, lengths, ...) and post layout simulations and full system verifications. In the latter two cases, systems of coupled models are considered. In post layout simulations one has to deal with artificial, parasitic circuits, describing wiring effects.

Model Order Reduction automatically captures the essential features of a structure, omitting information which are not decisive for the answer to the above questions. Model Order reduction replaces in this way a dynamical system with another dynamical system producing (almost) the same output, given the same input with less internal states.

MOR replaces high dimensional (e.g. millions of degrees of freedom) with low dimensional (e.g. a hundred of degrees of freedom ) problems, that are then used instead in the numerical simulation.

The working group "Applied Mathematics/Numerical Analysis" has gathered expertise in MOR, especially in circuit design. Within the EU-Marie Curie Initial Training Network COMSON, attention was concentrated on MOR for Differential Algebraic Equations. Members that have been working on MOR in the EU-Marie Curie Transfer of Knowledge project O-MOORE-NICE! gathered knowledge especially in the still immature field of MOR for nonlinear problems.

Current research topics include:

  • MOR for nonlinear, parameterized problems
  • structure preserving MOR
  • MOR for Differential Algebraic Equations
  • MOR in financial applications, i.e., option prizing

Group members working on that field

  • Jan ter Maten
  • Roland Pulch

Publications



2023

5118.

Ehrhardt, Matthias
Mathematical Analysis and a Nonstandard Scheme for a Model of the Immune Response against COVID-19
2023

5117.


Measurement of $t$-channel production of single top quarks and antiquarks in $pp$ collisions at 13 TeV using the full ATLAS Run 2 dataset
2023

5116.

Mayotte, Eric William; others
Measurement of the mass composition of ultra-high-energy cosmic rays at the Pierre Auger Observatory
PoS, ICRC2023 :365
2023

5115.

[german] Grandrath, Rebecca; Bohrmann-Linde, Claudia
Mit Lactase und Lactose zum elektrischen Strom - enzymatische Brennstoffzellen auf Filterpapierbasis für den Chemieunterricht.
CHEMKON, 30 (1) :37-41
January 2023

5114.

Jäschke, Jens; Skrepek, Nathanael; Ehrhardt, Matthias
Mixed-dimensional geometric coupling of port-Hamiltonian systems
Applied Mathematics Letters, 137 :108508
2023
Publisher: Pergamon

5113.

Jäschke, Jens; Skrepek, Nathanael; Ehrhardt, Matthias
Mixed-dimensional geometric coupling of port-Hamiltonian systems
Applied Mathematics Letters, 137 :108508
2023
Publisher: Pergamon

5112.

Jäschke, Jens; Skrepek, Nathanael; Ehrhardt, Matthias
Mixed-dimensional geometric coupling of port-Hamiltonian systems
Applied Mathematics Letters, 137 :108508
2023
Publisher: Pergamon

5111.

Klamroth, Kathrin; Stiglmayr, Michael; Sudhoff, Julia
Multi-objective matroid optimization with ordinal weights
Discrete Applied Mathematics, 335 :104-119
2023
ISSN: 0166-218X

5110.

Vinod, Vivin; Maity, Sayan; Zaspel, Peter; Kleinekathöfer, Ulrich
Multifidelity Machine Learning for Molecular Excitation Energies
J. Chem. Theory Comput., 19 (21) :7658-7670
2023

5109.

Beck, Christian; Jentzen, Arnulf; Kleinberg, Konrad; Kruse, Thomas
Nonlinear Monte Carlo methods with polynomial runtime for Bellman equations of discrete time high-dimensional stochastic optimal control problems
Preprint
2023

5108.

Beck, Christian; Jentzen, Arnulf; Kleinberg, Konrad; Kruse, Thomas
Nonlinear Monte Carlo methods with polynomial runtime for Bellman equations of discrete time high-dimensional stochastic optimal control problems
2023

5107.

Müller, Mats; Kemper, Svenja; Schlenkhoff, Andreas
Numerical modelling of the hydraulic capacity of grates inlets (OpenFOAM)
E-proceedings of the 40th IAHR World Congress in 2023 in Vienna, Austria.
2023

5106.

Finster, Rebecca; Kronschläger, Thomas; Grogorick, Linda; Robra-Bissantz, Susanne
Ok, gegen Cupids Pfeil hilft keine Firewall – Sichere(s) Daten durch ganzheitlichen Kompetenzaufbau
HMD - Praxis der Wirtschaftsinformatik, 61 :27–42
2023

5105.

Ehrhardt, Matthias; Kozitskiy, Sergey B
On a generalization of the split-step Padé method to the case of unknown vector-functions
Preprint IMACM
2023
Publisher: Bergische Universität Wuppertal

5104.

Ehrhardt, Matthias; Kozitskiy, Sergey B
On a generalization of the split-step Padé method to the case of unknown vector-functions
Preprint IMACM
2023
Publisher: Bergische Universität Wuppertal

5103.

Farkas, Bálint; Jacob, Birgit; Schmitz, Merlin
On exponential splitting methods for semilinear abstract Cauchy problems
Integral Equations and Operator Theory, 95 :Paper No. 15
2023

5102.

Kraus, Konstantin; Klamroth, Kathrin; Stiglmayr, Michael
On the online path extension problem -- Location and routing problems in board games
2023

5101.

Bartel, Andreas; Günther, Michael; Jacob, Birgit; Reis, Timo
Operator splitting based dynamic iteration for linear differential-algebraic port-Hamiltonian systems
Accepted at Numerische Mathematik
2023

5100.

Bartel, Andreas; Günther, Michael; Jacob, Birgit; Reis, Timo
Operator splitting based dynamic iteration for linear differential-algebraic port-Hamiltonian systems
Numerische Mathematik, 155 (1-2) :1–34
2023
Publisher: Springer New York

5099.

Bartel, Andreas; Günther, Michael; Jacob, Birgit; Reis, Timo
Operator splitting based dynamic iteration for linear differential-algebraic port-Hamiltonian systems
Numerische Mathematik, 155 (1-2) :1–34
2023
Publisher: Springer New York

5098.

Bartel, A.; Günther, M.; Jacob, Birgit; Reis, T.
Operator splitting based dynamic iteration for linear differential-algebraic port-Hamiltonian systems
Numer. Math., 155 (1-2) :1-34
2023

5097.

Farkas, Bálint; Jacob, Birgit; Reis, Timo; Schmitz, Merlin
Operator splitting based dynamic iteration for linear infinite-dimensional port-Hamiltonian systems
2023

5096.

Frommer, Andreas; Günther, Michael; Liljegren-Sailer, Björn; Marheineke, Nicole
Operator splitting for port-Hamiltonian systems
arXiv preprint arXiv:2304.01766
2023

5095.

Frommer, Andreas; Günther, Michael; Liljegren-Sailer, Björn; Marheineke, Nicole
Operator splitting for port-Hamiltonian systems
Preprint
2023

5094.

Frommer, Andreas; Günther, Michael; Liljegren-Sailer, Björn; Marheineke, Nicole
Operator splitting for port-Hamiltonian systems
Preprint
2023