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
- 1979
17.
Barnes, Ian; Becker, Karl Heinz; Fink, Ewald H.
Chemiluminescence of SO(1Δg,1Σg+) sensitized by O2(1Δg)
Chemical Physics Letters, 67 (2-3) :310-313
197916.
Barnes, Ian; Becker, Karl Heinz; Fink, Ewald H.
Near-infrared emissions from the \(^{1}\)\(\Delta\)\(_{g}\) and \(^{1}\)\(\Sigma\)\(_{g}\)\(^{+}\) states of S\(_{2}\)
Chemical Physics Letters, 67 (2-3) :314-317
197915.
Barnes, Ian; Becker, Karl Heinz; Fink, Ewald H.
Near-infrared emissions from the \(^{1}\)\(\Delta\)\(_{g}\) and \(^{1}\)\(\Sigma\)\(_{g}\)\(^{+}\) states of S\(_{2}\)
Chemical Physics Letters, 67 (2-3) :314-317
197914.
Barnes, Ian; Becker, Karl Heinz; Fink, Ewald H.
Near-infrared emissions from the 1Δg and 1Σg+ states of S2
Chemical Physics Letters, 67 (2-3) :314-317
197913.
Tausch, Michael W.
Vorschlag für den Aufbau und die Bewertung einer Klausur zum Kurs ''Bindung und Struktur''
Praxis der Naturwissenschaften (Chemie), 28 :304
1979- 1978
12.
Tausch, Michael W.; C. Hass, E.; J. Plath, P.
Eine graphentheoretische Bezugsstruktur für die Eigenwertsumme konjugierter Kohlenwasserstoffe
Bremer Briefe zur Chemie, 2 (30)
197811.
Leiss, A.; Schurath, Ulrich; Becker, Karl Heinz; Fink, Ewald H.
Revised quenching rate constants for metastable oxygen molecules O\(_{2}\)(a\(^{1}\)\(\Delta\)\(_{g}\))
Journal of Photochemistry, 8 (2) :211-214
197810.
Leiss, A.; Schurath, Ulrich; Becker, Karl Heinz; Fink, Ewald H.
Revised quenching rate constants for metastable oxygen molecules O\(_{2}\)(a\(^{1}\)\(\Delta\)\(_{g}\))
Journal of Photochemistry, 8 (2) :211-214
19789.
Leiss, A.; Schurath, Ulrich; Becker, Karl Heinz; Fink, Ewald H.
Revised quenching rate constants for metastable oxygen molecules O2(a1Δg)
Journal of Photochemistry, 8 (2) :211-214
1978- 1977
8.
[german] Tausch, Michael W.; Elian, Mihai; Bucur, Aurora; Cior{{\^a}}nescu, Ecaterina
Über das photochemische Verhalten von zwei Tribenzo-(CH)12-Valenzisomeren
Chemische Berichte, 110 (5) :1744-1747
1977
Publisher: Wiley- 1974
7.
Mihail, R.; Tausch, Michael W.
Homogene Reaktionen in einem Rohrreaktor mit nicht-Newtonscher Strömung
The Chemical Engineering Journal, 7 (1) :53--60
1974
Publisher: Elsevier {BV}6.
Becker, Karl Heinz; Fink, Ewald H.; Langen, P.; Schurath, Ulrich
Near infrared emission bands of the HO\(_{2}\) radical
The Journal of Chemical Physics, 60 (11) :4623-4625
19745.
Becker, Karl Heinz; Fink, Ewald H.; Langen, P.; Schurath, Ulrich
Near infrared emission bands of the HO\(_{2}\) radical
The Journal of Chemical Physics, 60 (11) :4623-4625
19744.
Becker, Karl Heinz; Fink, Ewald H.; Langen, P.; Schurath, Ulrich
Near infrared emission bands of the HO2 radical
The Journal of Chemical Physics, 60 (11) :4623-4625
1974- 1973
3.
Becker, Karl Heinz; Fink, Ewald H.; Langen, P.; Schurath, Ulrich
The Chemiluminescent Reaction of HCO with O\(_{2}\)(\(^{1}\)\(\Delta\)\(_{g}\))
Zeitschrift für Naturforschung A, 28 (11) :1872-1874
19732.
Becker, Karl Heinz; Fink, Ewald H.; Langen, P.; Schurath, Ulrich
The Chemiluminescent Reaction of HCO with O\(_{2}\)(\(^{1}\)\(\Delta\)\(_{g}\))
Zeitschrift für Naturforschung A, 28 (11) :1872-1874
19731.
Becker, Karl Heinz; Fink, Ewald H.; Langen, P.; Schurath, Ulrich
The Chemiluminescent Reaction of HCO with O2(1Δg)
Zeitschrift für Naturforschung A, 28 (11) :1872-1874
1973