Applied and Computational Mathematics (ACM)

Index Analysis

DAEs are no ODEs. Actually, Differential agebraic equations (DAEs) are a mixture of ordinary differential equations (ODEs) and algebraic relations. This may create difficulties, which are not seen at the first sight. The analysis shows that due this mixture hidden differentiation might occur. Recalling from analysis that differentiation is not an unbounded operator, such a process is much more difficult to handle than the integrals used for solving ODEs. E.g. imagine a sinosoidal signal of small amplitude but with high frequency, such as a numerical error, the derivative is of much larger magnitude.

Clearly, the more derivatives involved in the exact solution of a DAE, the more one needs to be careful in numerical computations. The index is a measure for this difficutly. That is why it is important to know the index before simulation.

Group members working on that field

  • Andreas Bartel
  • Michael Günther

 

Cooperations

  • Giuseppe Ali (Academia)
  • Sascha Baumanns (Academia)
  • Caren Tischendorf (Academia)

Publications



1991

342.

Jensen, Per; Oddershede, Jens; Sabin, John R.
Geometric dependence of the mean excitation energy and spectral moments of water
Physical Review A, 43 (7) :4040-4043
1991

341.

Jensen, Per; Oddershede, Jens; Sabin, John R.
Geometric dependence of the mean excitation energy and spectral moments of water
Physical Review A, 43 (7) :4040-4043
1991

340.

Jensen, Per; Oddershede, Jens; Sabin, John R.
Geometric dependence of the mean excitation energy and spectral moments of water
Physical Review A, 43 (7) :4040-4043
1991

339.

Becker, Karl Heinz; Geiger, Harald; Wiesen, Peter
Kinetic study of the OH radical chain in the reaction system OH + C\(_{2}\)H\(_{4}\) + NO + air
Chemical Physics Letters, 184 (4) :256-261
1991

338.

Becker, Karl Heinz; Geiger, Harald; Wiesen, Peter
Kinetic study of the OH radical chain in the reaction system OH + C\(_{2}\)H\(_{4}\) + NO + air
Chemical Physics Letters, 184 (4) :256-261
1991

337.

Becker, Karl Heinz; Geiger, Harald; Wiesen, Peter
Kinetic study of the OH radical chain in the reaction system OH + C2H4 + NO + air
Chemical Physics Letters, 184 (4) :256-261
1991

336.

Wildt, J{ü}rgen; Bednarek, G.; Fink, Ewald H.; Wayne, Richard P.
Laser excitation of the A\(^{3}\)\(\Sigma\)\(_{u}\)\(^{+}\), A'\(^{3}\)\(\Delta\)\(_{u}\) and c\(^{1}\)\(\Sigma\)\(_{u}\)\(^{-}\) states of molecular oxygen
Chemical Physics, 156 (3) :497-508
1991

335.

Wildt, J{ü}rgen; Bednarek, G.; Fink, Ewald H.; Wayne, Richard P.
Laser excitation of the A\(^{3}\)\(\Sigma\)\(_{u}\)\(^{+}\), A'\(^{3}\)\(\Delta\)\(_{u}\) and c\(^{1}\)\(\Sigma\)\(_{u}\)\(^{-}\) states of molecular oxygen
Chemical Physics, 156 (3) :497-508
1991

334.

Wildt, Jürgen; Bednarek, G.; Fink, Ewald H.; Wayne, Richard P.
Laser excitation of the A3Σu+, A'3Δu and c1Σu- states of molecular oxygen
Chemical Physics, 156 (3) :497-508
1991

333.

Tausch, Michael W.
Legende oder nicht Legende?
Praxis der Naturwissenschaften (Chemie), 40 :44
1991

332.

Benter, Thorsten; Becker, Eilhard; Wille, Uta; Schindler, Ralph N.; Canosa-Mas, Carlos E.; Smith, Stuart J.; Waygood, Steven J.; Wayne, Richard P.
Nitrate radical reactions: interactions with alkynes
Journal of the Chemical Society, Faraday Transactions, 87 (14) :2141
1991

331.

Benter, Thorsten; Becker, Eilhard; Wille, Uta; Schindler, Ralph N.; Canosa-Mas, Carlos E.; Smith, Stuart J.; Waygood, Steven J.; Wayne, Richard P.
Nitrate radical reactions: interactions with alkynes
Journal of the Chemical Society, Faraday Transactions, 87 (14) :2141
1991

330.

Benter, Thorsten; Becker, Eilhard; Wille, Uta; Schindler, Ralph N.; Canosa-Mas, Carlos E.; Smith, Stuart J.; Waygood, Steven J.; Wayne, Richard P.
Nitrate radical reactions: interactions with alkynes
Journal of the Chemical Society, Faraday Transactions, 87 (14) :2141
1991

329.

[german] Tausch, Michael W.
Photochemie - aktuelle Bedeutung und Möglichkeiten der Integration in den Chemieunterricht
Praxis der Naturwissenschaften (Chemie), 40 (4) :2
1991

328.

Becker, Karl Heinz; Kurtenbach, Ralf; Wiesen, Peter
Temperature and pressure dependence of the reaction methylidyne radical + hydrogen
The Journal of Physical Chemistry, 95 (6) :2390-2394
1991

327.

Becker, Karl Heinz; Kurtenbach, Ralf; Wiesen, Peter
Temperature and pressure dependence of the reaction methylidyne radical + hydrogen
The Journal of Physical Chemistry, 95 (6) :2390-2394
1991

326.

Becker, Karl Heinz; Kurtenbach, Ralf; Wiesen, Peter
Temperature and pressure dependence of the reaction methylidyne radical + hydrogen
The Journal of Physical Chemistry, 95 (6) :2390-2394
1991

325.

Bunker, Philip R.; Jensen, Per; Karpfen, Alfred
The \(\nu\)\(_{1}\) + \(\nu\)\(_{2}\) = 4 stretching overtones of the HF dimer, and H-atom exchange
Journal of Molecular Spectroscopy, 149 (2) :512-518
1991

324.

Bunker, Philip R.; Jensen, Per; Karpfen, Alfred
The \(\nu\)\(_{1}\) + \(\nu\)\(_{2}\) = 4 stretching overtones of the HF dimer, and H-atom exchange
Journal of Molecular Spectroscopy, 149 (2) :512-518
1991

323.

Fink, Ewald H.; Setzer, Klaus-Dieter; Ramsay, D. A.; Vervloet, M.
The X\(_{2}\)\(^{2}\)\(\Pi\)\(_{1/2}\) → X\(_{1}\)\(^{2}\)\(\Pi\)\(_{3/2}\) electronic transitions of tellurium monohalides in the near infrared
Chemical Physics Letters, 177 (3) :265-268
1991

322.

Fink, Ewald H.; Setzer, Klaus-Dieter; Ramsay, D. A.; Vervloet, M.
The X\(_{2}\)\(^{2}\)\(\Pi\)\(_{1/2}\) → X\(_{1}\)\(^{2}\)\(\Pi\)\(_{3/2}\) electronic transitions of tellurium monohalides in the near infrared
Chemical Physics Letters, 177 (3) :265-268
1991

321.

Fink, Ewald H.; Setzer, Klaus-Dieter; Ramsay, D. A.; Vervloet, M.
The X\(_{2}\)1 → X\(_{1}\)0\(^{+}\) electronic band systems of bismuth monohalides in the near infrared
Chemical Physics Letters, 179 (1-2) :95-102
1991

320.

Fink, Ewald H.; Setzer, Klaus-Dieter; Ramsay, D. A.; Vervloet, M.
The X\(_{2}\)1 → X\(_{1}\)0\(^{+}\) electronic band systems of bismuth monohalides in the near infrared
Chemical Physics Letters, 179 (1-2) :95-102
1991

319.

Fink, Ewald H.; Setzer, Klaus-Dieter; Ramsay, D. A.; Vervloet, M.
The X22Π1/2 → X12Π3/2 electronic transitions of tellurium monohalides in the near infrared
Chemical Physics Letters, 177 (3) :265-268
1991

318.

Fink, Ewald H.; Setzer, Klaus-Dieter; Ramsay, D. A.; Vervloet, M.
The X21 → X10+ electronic band systems of bismuth monohalides in the near infrared
Chemical Physics Letters, 179 (1-2) :95-102
1991