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



2006

1543.

Stemmler, Konrad; Ammann, Markus; Donders, Chantal; Kleffmann, Jörg; George, Christian
Photosensitized reduction of nitrogen dioxide on humic acid as a source of nitrous acid
Nature, 440 (7081) :195-198
2006
Publisher: Nature Publishing Group

1542.

Stemmler, Konrad; Ammann, Markus; Donders, Chantal; Kleffmann, Jörg; George, Christian
Photosensitized reduction of nitrogen dioxide on humic acid as a source of nitrous acid
Nature, 440 (7081) :195-198
2006
Publisher: Nature Publishing Group

1541.

Farkas, Bálint; Révész, Szilárd Gy.
Potential theoretic approach to rendezvous numbers
Monatsh. Math., 148 (4) :309-331
2006

1540.

Short, Luke Chandler; Benter, Thorsten
Principles of solution thermodynamics: Demonstration of nonideal behavior of Henry's law. An undergraduate laboratory experiment
Journal of Chemical Education, 83 (8) :1233-1236
2006

1539.

Short, Luke Chandler; Benter, Thorsten
Principles of solution thermodynamics: Demonstration of nonideal behavior of Henry's law. An undergraduate laboratory experiment
Journal of Chemical Education, 83 (8) :1233-1236
2006

1538.

Short, Luke Chandler; Benter, Thorsten
Principles of solution thermodynamics: Demonstration of nonideal behavior of Henry's law. An undergraduate laboratory experiment
Journal of Chemical Education, 83 (8) :1233-1236
2006

1537.

Zhou, Shouming; Barnes, Ian; Zhu, Tong; Klotz, Bj{ö}rn; Albu, Mihaela; Bejan, Iustinian; Benter, Thorsten
Product study of the OH, NO\(_{3}\), and O\(_{3}\) initiated atmospheric photooxidation of propyl vinyl ether
Environmental Science and Technology, 40 (17) :5415-5421
2006

1536.

Zhou, Shouming; Barnes, Ian; Zhu, Tong; Klotz, Bj{ö}rn; Albu, Mihaela; Bejan, Iustinian; Benter, Thorsten
Product study of the OH, NO\(_{3}\), and O\(_{3}\) initiated atmospheric photooxidation of propyl vinyl ether
Environmental Science and Technology, 40 (17) :5415-5421
2006

1535.

Zhou, Shouming; Barnes, Ian; Zhu, Tong; Klotz, Björn; Albu, Mihaela; Bejan, Iustinian; Benter, Thorsten
Product study of the OH, NO3, and O3 initiated atmospheric photooxidation of propyl vinyl ether
Environmental Science and Technology, 40 (17) :5415-5421
2006

1534.

Albu, Mihaela; Barnes, Ian; Becker, Karl Heinz; Patroescu-Klotz, Iulia; Mocanu, Raluca; Benter, Thorsten
Rate coefficients for the gas-phase reaction of OH radicals with dimethyl sulfide: Temperature and O\(_{2}\) partial pressure dependence
Physical Chemistry Chemical Physics, 8 (6) :728-736
2006

1533.

Albu, Mihaela; Barnes, Ian; Becker, Karl Heinz; Patroescu-Klotz, Iulia; Mocanu, Raluca; Benter, Thorsten
Rate coefficients for the gas-phase reaction of OH radicals with dimethyl sulfide: Temperature and O\(_{2}\) partial pressure dependence
Physical Chemistry Chemical Physics, 8 (6) :728-736
2006

1532.

Albu, Mihaela; Barnes, Ian; Becker, Karl Heinz; Patroescu-Klotz, Iulia; Mocanu, Raluca; Benter, Thorsten
Rate coefficients for the gas-phase reaction of OH radicals with dimethyl sulfide: Temperature and O2 partial pressure dependence
Physical Chemistry Chemical Physics, 8 (6) :728-736
2006

1531.

Solignac, G.; Mellouki, Abdelwahid; Le Bras, G.; Barnes, Ian; Benter, Thorsten
Reaction of Cl atoms with C\(_{6}\)F\(_{13}\)CH\(_{2}\)OH, C\(_{6}\)F\(_{13}\)CHO, and C\(_{3}\)F\(_{7}\)CHO
Journal of Physical Chemistry A, 110 (13) :4450-4457
2006

1530.

Solignac, G.; Mellouki, Abdelwahid; Le Bras, G.; Barnes, Ian; Benter, Thorsten
Reaction of Cl atoms with C\(_{6}\)F\(_{13}\)CH\(_{2}\)OH, C\(_{6}\)F\(_{13}\)CHO, and C\(_{3}\)F\(_{7}\)CHO
Journal of Physical Chemistry A, 110 (13) :4450-4457
2006

1529.

Solignac, G.; Mellouki, Abdelwahid; Le Bras, G.; Barnes, Ian; Benter, Thorsten
Reaction of Cl atoms with C6F13CH2OH, C6F13CHO, and C3F7CHO
Journal of Physical Chemistry A, 110 (13) :4450-4457
2006

1528.

Spittler, M.; Barnes, Ian; Bejan, Iustinian; Brockmann, Klaus Josef; Benter, Thorsten; Wirtz, K.
Reactions of NO\(_{3}\) radicals with limonene and \(\alpha\)-pinene: Product and SOA formation
Atmospheric Environment, 40 :116-127
2006
Publisher: Pergamon

1527.

Spittler, M.; Barnes, Ian; Bejan, Iustinian; Brockmann, Klaus Josef; Benter, Thorsten; Wirtz, K.
Reactions of NO\(_{3}\) radicals with limonene and \(\alpha\)-pinene: Product and SOA formation
Atmospheric Environment, 40 :116-127
2006
Publisher: Pergamon

1526.

Spittler, M.; Barnes, Ian; Bejan, Iustinian; Brockmann, Klaus Josef; Benter, Thorsten; Wirtz, K.
Reactions of NO\(_{3}\) radicals with limonene and alpha-pinene: Product and SOA formation
Atmospheric Environment, 40 (1) :S116-S127
2006

1525.

Spittler, M.; Barnes, Ian; Bejan, Iustinian; Brockmann, Klaus Josef; Benter, Thorsten; Wirtz, K.
Reactions of NO\(_{3}\) radicals with limonene and alpha-pinene: Product and SOA formation
Atmospheric Environment, 40 (1) :S116-S127
2006

1524.

Spittler, M.; Barnes, Ian; Bejan, Iustinian; Brockmann, Klaus Josef; Benter, Thorsten; Wirtz, K.
Reactions of NO3 radicals with limonene and alpha-pinene: Product and SOA formation
Atmospheric Environment, 40 (1) :S116-S127
2006

1523.

Spittler, M.; Barnes, Ian; Bejan, Iustinian; Brockmann, Klaus Josef; Benter, Thorsten; Wirtz, K.
Reactions of NO3 radicals with limonene and α-pinene: Product and SOA formation
Atmospheric Environment, 40 :116-127
2006
Publisher: Pergamon

1522.

Short, Luke Chandler; Frey, Rüdiger; Benter, Thorsten
Real-Time Analysis of Exhaled Breath via Resonance-Enhanced Multiphoton Ionization-Mass Spectrometry with a Medium Pressure Laser Ionization Source: Observed Nitric Oxide Profile
Applied Spectroscopy, 60 (2) :217-222
2006
Publisher: SAGE PublicationsSage UK: London, England

1521.

Short, Luke Chandler; Frey, R{ü}diger; Benter, Thorsten
Real-Time Analysis of Exhaled Breath via Resonance-Enhanced Multiphoton Ionization-Mass Spectrometry with a Medium Pressure Laser Ionization Source: Observed Nitric Oxide Profile
Applied Spectroscopy, 60 (2) :217-222
2006
Publisher: SAGE PublicationsSage UK: London, England

1520.

Short, Luke Chandler; Frey, R{ü}diger; Benter, Thorsten
Real-Time Analysis of Exhaled Breath via Resonance-Enhanced Multiphoton Ionization-Mass Spectrometry with a Medium Pressure Laser Ionization Source: Observed Nitric Oxide Profile
Applied Spectroscopy, 60 (2) :217-222
2006
Publisher: SAGE PublicationsSage UK: London, England

1519.

Farkas, Bálint; Révész, Szilárd Gy.
Rendezvous numbers of metric spaces--a potential theoretic approach
Arch. Math. (Basel), 86 (3) :268-281
2006