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



1982

42.

Jensen, Per; Bunker, Philip R.
The geometry and the out-of-plane bending potential function of thioformaldehyde in the A\verb=~=\(^{1}\)A\(_{2}\) and a\verb=~=\(^{3}\)A\(_{2}\) electronic states
Journal of Molecular Spectroscopy, 95 (1) :92-100
1982

41.

Jensen, Per; Bunker, Philip R.
The geometry and the out-of-plane bending potential function of thioformaldehyde in the A~1A2 and a~3A2 electronic states
Journal of Molecular Spectroscopy, 95 (1) :92-100
1982

40.

Jensen, Per; Brodersen, Svend
The ν5 Raman band of CH3CD3
Journal of Raman Spectroscopy, 12 (3) :295-299
1982

39.

Tausch, Michael W.; J. Plath, P.
Umlagerungen in (CH)₇⁺-Carbokationen
Revue Roumaine de Chimie, 27 :953
1982
1981

38.

Tausch, Michael W.
BINDUNG UND STRUKTUR - Unterrichtsbuch für die gymnasiale Oberstufe
Publisher: Schöningh, Paderborn
1981

37.

Jensen, Per; Brodersen, Svend; Guelachvili, Guy
Determination of A\(_{0}\) for CH\(_{3}\)\(^{35}\)Cl and CH\(_{3}\)\(^{37}\)Cl from the \(\nu\)\(_{4}\) infrared and Raman bands
Journal of Molecular Spectroscopy, 88 (2) :378-393
1981

36.

Jensen, Per; Brodersen, Svend; Guelachvili, Guy
Determination of A\(_{0}\) for CH\(_{3}\)\(^{35}\)Cl and CH\(_{3}\)\(^{37}\)Cl from the \(\nu\)\(_{4}\) infrared and Raman bands
Journal of Molecular Spectroscopy, 88 (2) :378-393
1981

35.

Jensen, Per; Brodersen, Svend; Guelachvili, Guy
Determination of A0 for CH335Cl and CH337Cl from the ν4 infrared and Raman bands
Journal of Molecular Spectroscopy, 88 (2) :378-393
1981

34.

Barnes, Ian; Bastian, V.; Becker, Karl Heinz; Fink, Ewald H.; Zabel, Friedhelm
Rate constant of the reaction of OH with HO\(_{2}\)NO\(_{2}\)
Chemical Physics Letters, 83 (3) :459-464
1981

33.

Barnes, Ian; Bastian, V.; Becker, Karl Heinz; Fink, Ewald H.; Zabel, Friedhelm
Rate constant of the reaction of OH with HO\(_{2}\)NO\(_{2}\)
Chemical Physics Letters, 83 (3) :459-464
1981

32.

Barnes, Ian; Bastian, V.; Becker, Karl Heinz; Fink, Ewald H.; Zabel, Friedhelm
Rate constant of the reaction of OH with HO2NO2
Chemical Physics Letters, 83 (3) :459-464
1981

31.

Tausch, Michael W.
THEORETISCHE UND EXPERIMENTELLE UNTERSUCHUNGEN VON VALENZISOMERISIERUNGEN
Publisher: Minerva Publikation, München
1981

30.

Tausch, Michael W.
Vorschlag für den Aufbau und die Bewertung einer Klausur zum Kurs ''Grundreaktionen in der organischen Chemie"
Praxis der Naturwissenschaften (Chemie), 30 :374
1981
1980

29.

Winter, R.; Barnes, Ian; Fink, Ewald H.; Wildt, J{ü}rgen; Zabel, Friedhelm
b\(^{1}\)\(\Sigma\)\(^{+}\) → X\(^{3}\)\(\Sigma\)\(^{-}\) Emissions of SeO, SeS, and Se\(_{2}\) in the near infrared
Chemical Physics Letters, 73 (2) :297-303
1980

28.

Winter, R.; Barnes, Ian; Fink, Ewald H.; Wildt, J{ü}rgen; Zabel, Friedhelm
b\(^{1}\)\(\Sigma\)\(^{+}\) → X\(^{3}\)\(\Sigma\)\(^{-}\) Emissions of SeO, SeS, and Se\(_{2}\) in the near infrared
Chemical Physics Letters, 73 (2) :297-303
1980

27.

Winter, R.; Barnes, Ian; Fink, Ewald H.; Wildt, Jürgen; Zabel, Friedhelm
b1Σ+ → X3Σ- Emissions of SeO, SeS, and Se2 in the near infrared
Chemical Physics Letters, 73 (2) :297-303
1980

26.

Kauppinen, Jyrki; Jensen, Per; Brodersen, Svend
Determination of the B\(_{0}\) constant of C\(_{6}\)H\(_{6}\)
Journal of Molecular Spectroscopy, 83 (1) :161-174
1980

25.

Kauppinen, Jyrki; Jensen, Per; Brodersen, Svend
Determination of the B\(_{0}\) constant of C\(_{6}\)H\(_{6}\)
Journal of Molecular Spectroscopy, 83 (1) :161-174
1980

24.

Kauppinen, Jyrki; Jensen, Per; Brodersen, Svend
Determination of the B0 constant of C6H6
Journal of Molecular Spectroscopy, 83 (1) :161-174
1980
1979

23.

Glaschick-Schimpf, I.; Leiss, A.; Monkhouse, Penelope B.; Schurath, Ulrich; Becker, Karl Heinz; Fink, Ewald H.
A kinetic study of the reactions of HO\(_{2}\)/DO\(_{2}\) radicals with nitric oxide using near-infrared chemiluminescence detection
Chemical Physics Letters, 67 (2-3) :318-323
1979

22.

Glaschick-Schimpf, I.; Leiss, A.; Monkhouse, Penelope B.; Schurath, Ulrich; Becker, Karl Heinz; Fink, Ewald H.
A kinetic study of the reactions of HO\(_{2}\)/DO\(_{2}\) radicals with nitric oxide using near-infrared chemiluminescence detection
Chemical Physics Letters, 67 (2-3) :318-323
1979

21.

Glaschick-Schimpf, I.; Leiss, A.; Monkhouse, Penelope B.; Schurath, Ulrich; Becker, Karl Heinz; Fink, Ewald H.
A kinetic study of the reactions of HO2/DO2 radicals with nitric oxide using near-infrared chemiluminescence detection
Chemical Physics Letters, 67 (2-3) :318-323
1979

20.

Tausch, Michael W.; C. Ha{ßs}, E.; J. Plath, P.
Beschreibung von Valenzisomerisierungen durch Strukturvariation auf vollständigen Graphen
Informal Communications in Mathematical Chemistry (MatCh), 7 :289
1979

19.

Barnes, Ian; Becker, Karl Heinz; Fink, Ewald H.
Chemiluminescence of SO(\(^{1}\)\(\Delta\)\(_{g}\),\(^{1}\)\(\Sigma\)\(_{g}\)\(^{+}\)) sensitized by O\(_{2}\)(\(^{1}\)\(\Delta\)\(_{g}\))
Chemical Physics Letters, 67 (2-3) :310-313
1979

18.

Barnes, Ian; Becker, Karl Heinz; Fink, Ewald H.
Chemiluminescence of SO(\(^{1}\)\(\Delta\)\(_{g}\),\(^{1}\)\(\Sigma\)\(_{g}\)\(^{+}\)) sensitized by O\(_{2}\)(\(^{1}\)\(\Delta\)\(_{g}\))
Chemical Physics Letters, 67 (2-3) :310-313
1979