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



2022

4767.

Günther, Michael; Sandu, Adrian
Multirate linearly-implicit GARK schemes
BIT Numerical Mathematics :869–901
2022
Herausgeber: Springer Netherlands

4766.

Bartel, Andreas; Günther, Michael
Multirate Schemes -- An Answer of Numerical Analysis to a Demand from Applications
In Michael Günther and Wil Schilders, Editor, Novel Mathematics Inspired by Industrial Challenges
Seite 5--27
Herausgeber: Springer
2022
5--27

4765.

Bartel, Andreas; Günther, Michael
Multirate schemes—an answer of numerical analysis to a demand from applications
In Günther, Michael and Schilders, Wil, Editor aus Mathematics in Industry
Seite 5–27
Herausgeber: Springer Cham
2022
5–27

4764.

Bartel, Andreas; Günther, Michael
Multirate schemes—an answer of numerical analysis to a demand from applications
Novel Mathematics Inspired by Industrial Challenges
Seite 5--27
Herausgeber: Springer International Publishing Cham
2022
5--27

4763.

Bartel, Andreas; Günther, Michael
Multirate schemes—an answer of numerical analysis to a demand from applications
In Günther, Michael and Schilders, Wil, Editor aus Mathematics in Industry
Seite 5–27
Herausgeber: Springer Cham
2022
5–27

4762.

Kapllani, Lorenc; Teng, Long
Multistep schemes for solving backward stochastic differential equations on {GPU}
JMI, 12 (5)
2022

4761.

Kapllani, Lorenc; Teng, Long
Multistep schemes for solving backward stochastic differential equations on GPU
Journal of Mathematics in Industry, 12 (1) :1–22
2022
Herausgeber: Springer Verlag

4760.

Fatoorehchi, Hooman; Ehrhardt, Matthias
Numerical and semi-nume\-rical solutions of a modified Thévenin model for calculating terminal voltage of battery cells
J. Energy Storage, 45 :103746
2022
Herausgeber: Elsevier

4759.

Fatoorehchi, Hooman; Ehrhardt, Matthias
Numerical and semi-numerical solutions of a modified Thévenin model for calculating terminal voltage of battery cells
Journal of Energy Storage, 45 :103746
2022
Herausgeber: Elsevier

4758.

Fatoorehchi, Hooman; Ehrhardt, Matthias
Numerical and semi-numerical solutions of a modified Thévenin model for calculating terminal voltage of battery cells
Journal of Energy Storage, 45 :103746
2022
Herausgeber: Elsevier

4757.

Fatoorehchi, Hooman; Ehrhardt, Matthias
Numerical and semi-numerical solutions of a modified Thévenin model for calculating terminal voltage of battery cells
Journal of Energy Storage, 45 :103746
2022
Herausgeber: Elsevier

4756.

Gerlach, Moritz; Glück, Jochen
On characteristics of the range of integral operators
2022

4755.

Ehrhardt, Matthias
On decomposition of the fundamental solution of the Helmholtz equation over solutions of iterative parabolic equations
Asymptotic Analysis, 126 (3-4) :215–228
2022
Herausgeber: IOS Press

4754.

Ehrhardt, Matthias
On decomposition of the fundamental solution of the Helmholtz equation over solutions of iterative parabolic equations
Asymptotic Analysis, 126 (3-4) :215–228
2022
Herausgeber: IOS Press

4753.

Ehrhardt, Matthias
On decomposition of the fundamental solution of the Helmholtz equation over solutions of iterative parabolic equations
Asymptotic Analysis, 126 (3-4) :215--228
2022
Herausgeber: IOS Press

4752.

Farkas, Bálint; Nagy, Béla; Révész, Szilárd Gy.
On intertwining of maxima of sum of translates functions with nonsingular kernels
Trudy Inst. Mat. Mekh. UrO RAN
2022

4751.

Jacob, Birgit; Morris, Kirsten
On solvability of dissipative partial differential-algebraic equations
IEEE Control. Syst. Lett., 6 :3188-3193
2022

4750.

Petrov, {Pavel S.}; Ehrhardt, Matthias; Trofimov, {M. Yu.}
On the decomposition of the fundamental solution of the {Helmholtz} equation via solutions of iterative parabolic equations
Asymptotic Analysis, 126 (3-4) :215--228
2022
Herausgeber: IOS Press

4749.

Hutzenthaler, Martin; Kruse, Thomas; Nguyen, Tuan Anh
On the speed of convergence of Picard iterations of BSDEs
Probability, Uncertainty and Quantitative Risk, 7 (2)
2022
Herausgeber: American Institute of Mathematical Sciences

4748.

Hutzenthaler, Martin; Kruse, Thomas; Nguyen, Tuan Anh
On the speed of convergence of Picard iterations of BSDEs
Probability, Uncertainty and Quantitative Risk, 7 (2)
2022
Herausgeber: American Institute of Mathematical Sciences

4747.

Hutzenthaler, Martin; Kruse, Thomas; Nguyen, Tuan Anh
On the speed of convergence of Picard iterations of BSDEs
Probability, Uncertainty and Quantitative Risk, 7 (2)
2022
Herausgeber: American Institute of Mathematical Sciences

4746.

Bartel, Andreas; Günther, Michael; Jacob, Birgit; Reis, Timo
Operator Splitting Based Dynamic Iteration for Linear Port-{H}amiltonian Systems
arXiv preprint arXiv:2208.03574
2022

4745.

Bartel, Andreas; Günther, Michael; Jacob, Birgit; Reis, Timo
Operator Splitting Based Dynamic Iteration for Linear Port-Hamiltonian Systems
arXiv preprint arXiv:2208.03574
2022

4744.

Sudhoff, Julia
Ordinal costs in multi-objective combinatorial optimization
Dissertation
Dissertation
Bergische Universität Wuppertal
2022

4743.

[german] Banerji, Amitabh; Dörschelln, Jennifer; Schwarz, D.
Organische Leuchtdioden im Chemieunterricht
Chemie in unserer Zeit, 52 (1) :34-41
2022