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
- 1986
167.
Kraemer, Wolfgang P.; Roos, B. O.; Bunker, Philip R.; Jensen, Per
An ab initio calculation of the rotation-vibration energies of the state of CCH using the nonrigid bender Hamiltonian
Journal of Molecular Spectroscopy, 120 (1) :236-238
1986166.
Fink, Ewald H.; Kruse, H.; Ramsay, D. A.; Vervloet, M.
An electric quadrupole transition: the emission system of oxygen
Canadian Journal of Physics, 64 (3) :242-245
1986
Publisher: NRC Research Press Ottawa, Canada165.
Fink, Ewald H.; Kruse, H.; Ramsay, D. A.; Vervloet, M.
An electric quadrupole transition: the emission system of oxygen
Canadian Journal of Physics, 64 (3) :242-245
1986
Publisher: NRC Research Press Ottawa, Canada164.
Fink, Ewald H.; Kruse, H.; Ramsay, D. A.; Vervloet, M.
An electric quadrupole transition: the emission system of oxygen
Canadian Journal of Physics, 64 (3) :242-245
1986
Publisher: NRC Research Press Ottawa, Canada163.
Jensen, Per; Winnewisser, Manfred
Prediction of higher inversion energy levels for isocyanamide H\(_{2}\)NNC
Collection of Czechoslovak Chemical Communications, 51 (7) :1373-1381
1986
Publisher: Institute of Organic Chemistry and Biochemistry AS CR, v.v.i.162.
Jensen, Per; Winnewisser, Manfred
Prediction of higher inversion energy levels for isocyanamide H\(_{2}\)NNC
Collection of Czechoslovak Chemical Communications, 51 (7) :1373-1381
1986
Publisher: Institute of Organic Chemistry and Biochemistry AS CR, v.v.i.161.
Jensen, Per; Winnewisser, Manfred
Prediction of higher inversion energy levels for isocyanamide H2NNC
Collection of Czechoslovak Chemical Communications, 51 (7) :1373-1381
1986
Publisher: Institute of Organic Chemistry and Biochemistry AS CR, v.v.i.160.
Bielefeld, M.; Wildt, J{ü}rgen; Fink, Ewald H.
Rate constants of the near-resonant E-E energy exchange processes SeS(b0\(^{+}\)) + O\(_{2}\)(X\(^{3}\)\(\Sigma\)\(_{g}\)\(^{-}\)) ↔ SeS(X\(_{1}\)0\(^{+}\)) + O\(_{2}\)(a\(^{1}\)\(\Delta\)\(_{g}\))
Chemical Physics Letters, 126 (5) :421-426
1986159.
Bielefeld, M.; Wildt, J{ü}rgen; Fink, Ewald H.
Rate constants of the near-resonant E-E energy exchange processes SeS(b0\(^{+}\)) + O\(_{2}\)(X\(^{3}\)\(\Sigma\)\(_{g}\)\(^{-}\)) ↔ SeS(X\(_{1}\)0\(^{+}\)) + O\(_{2}\)(a\(^{1}\)\(\Delta\)\(_{g}\))
Chemical Physics Letters, 126 (5) :421-426
1986158.
Bielefeld, M.; Wildt, Jürgen; Fink, Ewald H.
Rate constants of the near-resonant E-E energy exchange processes SeS(b0+) + O2(X3Σg-) ↔ SeS(X10+) + O2(a1Δg)
Chemical Physics Letters, 126 (5) :421-426
1986157.
Beardsworth, R.; Bunker, Philip R.; Jensen, Per; Kraemer, Wolfgang P.
Rotation-vibration energy levels of H\(_{2}\)O and C\(_{3}\) calculated using the nonrigid bender Hamiltonian
Journal of Molecular Spectroscopy, 118 (1) :50-63
1986156.
Beardsworth, R.; Bunker, Philip R.; Jensen, Per; Kraemer, Wolfgang P.
Rotation-vibration energy levels of H\(_{2}\)O and C\(_{3}\) calculated using the nonrigid bender Hamiltonian
Journal of Molecular Spectroscopy, 118 (1) :50-63
1986155.
Beardsworth, R.; Bunker, Philip R.; Jensen, Per; Kraemer, Wolfgang P.
Rotation-vibration energy levels of H2O and C3 calculated using the nonrigid bender Hamiltonian
Journal of Molecular Spectroscopy, 118 (1) :50-63
1986154.
Tausch, Michael W.
Silberfreie Photographie und Photochromie
Praxis der Naturwissenschaften (Chemie), 35 :19
1986153.
Maten, E. J. W.
Splitting methods for fourth order parabolic partial differential equations
Computing, 37 (4) :335--350
December 1986
Publisher: Springer Science and Business Media {LLC}152.
Fink, Ewald H.; Kruse, H.; Ramsay, D. A.
The high-resolution emission spectrum of S\(_{2}\) in the near infrared: The b\(^{1}\)\(\Sigma\)\(_{g}\)\(^{+}\) - X\(^{3}\)\(\Sigma\)\(_{g}\)\(^{-}\) system
Journal of Molecular Spectroscopy, 119 (2) :377-387
1986151.
Fink, Ewald H.; Kruse, H.; Ramsay, D. A.
The high-resolution emission spectrum of S\(_{2}\) in the near infrared: The b\(^{1}\)\(\Sigma\)\(_{g}\)\(^{+}\) - X\(^{3}\)\(\Sigma\)\(_{g}\)\(^{-}\) system
Journal of Molecular Spectroscopy, 119 (2) :377-387
1986150.
Fink, Ewald H.; Kruse, H.; Ramsay, D. A.
The high-resolution emission spectrum of S2 in the near infrared: The b1Σg+ - X3Σg- system
Journal of Molecular Spectroscopy, 119 (2) :377-387
1986149.
Jensen, Per; Johns, John W. C.
The infrared spectrum of carbon suboxide in the \(\nu\)\(_{6}\) fundamental region: Experimental observation and semirigid bender analysis
Journal of Molecular Spectroscopy, 118 (1) :248-266
1986148.
Jensen, Per; Johns, John W. C.
The infrared spectrum of carbon suboxide in the \(\nu\)\(_{6}\) fundamental region: Experimental observation and semirigid bender analysis
Journal of Molecular Spectroscopy, 118 (1) :248-266
1986147.
Jensen, Per; Johns, John W. C.
The infrared spectrum of carbon suboxide in the ν6 fundamental region: Experimental observation and semirigid bender analysis
Journal of Molecular Spectroscopy, 118 (1) :248-266
1986146.
Jensen, Per; Bunker, Philip R.
The nonrigid bender Hamiltonian using an alternative perturbation technique
Journal of Molecular Spectroscopy, 118 (1) :18-39
1986145.
Jensen, Per; Bunker, Philip R.
The nonrigid bender Hamiltonian using an alternative perturbation technique
Journal of Molecular Spectroscopy, 118 (1) :18-39
1986144.
Jensen, Per; Bunker, Philip R.
The nonrigid bender Hamiltonian using an alternative perturbation technique
Journal of Molecular Spectroscopy, 118 (1) :18-39
1986143.
Bunker, Philip R.; Jensen, Per; Kraemer, Wolfgang P.; Beardsworth, R.
The potential surface of X\verb=~=\(^{3}\)B\(_{1}\) methylene (CH\(_{2}\)) and the singlet-triplet splitting
The Journal of Chemical Physics, 85 (7) :3724-3731
1986