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
- 1998
757.
Schmidt, Sven; Benter, Thorsten; Schindler, Ralph N.
Photodissociation dynamcis of ClO radicals in the range (237<λ<270) nm and at 205 nm and the velocity distribution of O(1D) atoms
Chemical Physics Letters, 282 (3-4) :292-298
1998756.
Schmidt, Sven; Benter, Thorsten; Schindler, Ralph N.
Photodissociation dynamcis of ClO radicals in the range (237
Chemical Physics Letters, 282 (3-4) :292-298
1998755.
Schmidt, Sven; Benter, Thorsten; Schindler, Ralph N.
Photodissociation dynamcis of ClO radicals in the range (237
Chemical Physics Letters, 282 (3-4) :292-298
1998754.
Günther, Michael
Simulating digital circuits numerically - a charge-oriented ROW approach
Numerische Mathematik, 79 (2) :203–212
1998
Herausgeber: Springer New York753.
G\"unther, Michael
Simulating digital circuits numerically -- a charge-oriented {ROW} approach
Numer.~Math., 79 :203--212
1998752.
Günther, Michael
Simulating digital circuits numerically--a charge-oriented ROW approach
Numerische Mathematik, 79 (2) :203--212
1998
Herausgeber: Springer-Verlag751.
Tausch, Michael W.
Sinn(e) der Fachdidaktik
{CHEMKON}, 5 (4) :173--173
1998
Herausgeber: Wiley750.
Becker, Karl Heinz; Kleffmann, Jörg; Negri, R. Martin; Wiesen, Peter
Solubility of nitrous acid (HONO) in ammonium sulfate solutions
Journal of the Chemical Society - Faraday Transactions, 94 (11) :1583-1586
1998
Herausgeber: The Royal Society of Chemistry749.
Becker, Karl Heinz; Kleffmann, Jörg; Negri, R. Martin; Wiesen, Peter
Solubility of nitrous acid (HONO) in ammonium sulfate solutions
Journal of the Chemical Society - Faraday Transactions, 94 (11) :1583-1586
1998
Herausgeber: The Royal Society of Chemistry748.
Becker, Karl Heinz; Kleffmann, Jörg; Negri, R. Martin; Wiesen, Peter
Solubility of nitrous acid (HONO) in ammonium sulfate solutions
Journal of the Chemical Society - Faraday Transactions, 94 (11) :1583-1586
1998
Herausgeber: The Royal Society of Chemistry747.
[german] Tausch, Michael W.; Grolmuss, A.; Woock, M.
Vom Lichtquant zum Sehreiz
Praxis der Naturwissenschaften (Physik), 47 (5) :26
1998- 1997
746.
Arnold, A.; Ehrhardt, M.
A New Discrete Transparent Boundary Condition for Standard and Wide Angle 'Parabolic' Equations in Underwater Acoustics
Proceedings of the Third International Conference on Theoretical and Computational Acoustics, July 14-18, 1997, Newark, New Jersey, USA, Seite 623-635
1997745.
Ehrgott, Matthias; Hamacher, Horst W.; Klamroth, Kathrin; Nickel, Stefan; Schöbel, Anita; Wiecek, Margaret M.
A note on the equivalence of balance points and Pareto solutions in multiple objective programming
Journal of Optimization Theory and Applications, 92 :209-212
1997744.
G{{\'o}}mez, P. C.; Jensen, Per
A potential energy surface for the electronic ground state of H\(_{2}\)Te derived from experiment
Journal of Molecular Spectroscopy, 185 (2) :282-289
1997
Herausgeber: Academic Press743.
G{{\'o}}mez, P. C.; Jensen, Per
A potential energy surface for the electronic ground state of H\(_{2}\)Te derived from experiment
Journal of Molecular Spectroscopy, 185 (2) :282-289
1997
Herausgeber: Academic Press742.
Gómez, P. C.; Jensen, Per
A potential energy surface for the electronic ground state of H2Te derived from experiment
Journal of Molecular Spectroscopy, 185 (2) :282-289
1997
Herausgeber: Academic Press741.
Osmann, Gerald; Bunker, Philip R.; Jensen, Per; Kraemer, Wolfgang P.
A theoretical calculation of the absorption spectrum of CH\(_{2}\)\(^{+}\)
Chemical Physics, 225 (1-3) :33-54
1997
Herausgeber: North-Holland740.
Osmann, Gerald; Bunker, Philip R.; Jensen, Per; Kraemer, Wolfgang P.
A theoretical calculation of the absorption spectrum of CH\(_{2}\)\(^{+}\)
Chemical Physics, 225 (1-3) :33-54
1997
Herausgeber: North-Holland739.
Osmann, Gerald; Bunker, Philip R.; Jensen, Per; Kraemer, Wolfgang P.
A theoretical calculation of the absorption spectrum of CH2+
Chemical Physics, 225 (1-3) :33-54
1997
Herausgeber: North-Holland738.
Kozin, Igor N.; Jensen, Per; Li, Yan; Buenker, Robert J.; Hirsch, Gerhard; Klee, Stefan
An ab initio calculation of the dipole moment surfaces and the vibrational transition moments of the H\(_{2}\)Te molecule
Journal of Molecular Spectroscopy, 181 (1) :108-118
1997
Herausgeber: Academic Press737.
Kozin, Igor N.; Jensen, Per; Li, Yan; Buenker, Robert J.; Hirsch, Gerhard; Klee, Stefan
An ab initio calculation of the dipole moment surfaces and the vibrational transition moments of the H\(_{2}\)Te molecule
Journal of Molecular Spectroscopy, 181 (1) :108-118
1997
Herausgeber: Academic Press736.
Kozin, Igor N.; Jensen, Per; Li, Yan; Buenker, Robert J.; Hirsch, Gerhard; Klee, Stefan
An ab initio calculation of the dipole moment surfaces and the vibrational transition moments of the H2Te molecule
Journal of Molecular Spectroscopy, 181 (1) :108-118
1997
Herausgeber: Academic Press735.
Osmann, Gerald; Bunker, Philip R.; Jensen, Per; Kraemer, Wolfgang P.
An ab Initio Study of the NH\(_{2}\)\(^{+}\) Absorption Spectrum
Journal of Molecular Spectroscopy, 186 (2) :319-334
1997734.
Osmann, Gerald; Bunker, Philip R.; Jensen, Per; Kraemer, Wolfgang P.
An ab Initio Study of the NH\(_{2}\)\(^{+}\) Absorption Spectrum
Journal of Molecular Spectroscopy, 186 (2) :319-334
1997733.
Osmann, Gerald; Bunker, Philip R.; Jensen, Per; Kraemer, Wolfgang P.
An ab Initio Study of the NH2+ Absorption Spectrum
Journal of Molecular Spectroscopy, 186 (2) :319-334
1997