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

1986

157.

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
1986

DOI: 10.1016/0022-2852(86)90222-5

156.

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
1986

DOI: 10.1016/0022-2852(86)90222-5

155.

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
1986

DOI: 10.1016/0022-2852(86)90222-5

154.

Tausch, Michael W.
Silberfreie Photographie und Photochromie
Praxis der Naturwissenschaften (Chemie), 35 :19
1986

153.

Maten, E. J. W.
Splitting methods for fourth order parabolic partial differential equations
Computing, 37 (4) :335--350
Dezember 1986
Herausgeber: Springer Science and Business Media {LLC}

DOI: 10.1007/bf02251091

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
1986

DOI: 10.1016/0022-2852(86)90032-9

151.

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
1986

DOI: 10.1016/0022-2852(86)90032-9

150.

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
1986

DOI: 10.1016/0022-2852(86)90032-9

149.

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
1986

DOI: 10.1016/0022-2852(86)90239-0

148.

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
1986

DOI: 10.1016/0022-2852(86)90239-0

147.

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
1986

DOI: 10.1016/0022-2852(86)90239-0

146.

Jensen, Per; Bunker, Philip R.
The nonrigid bender Hamiltonian using an alternative perturbation technique
Journal of Molecular Spectroscopy, 118 (1) :18-39
1986

DOI: 10.1016/0022-2852(86)90220-1

145.

Jensen, Per; Bunker, Philip R.
The nonrigid bender Hamiltonian using an alternative perturbation technique
Journal of Molecular Spectroscopy, 118 (1) :18-39
1986

DOI: 10.1016/0022-2852(86)90220-1

144.

Jensen, Per; Bunker, Philip R.
The nonrigid bender Hamiltonian using an alternative perturbation technique
Journal of Molecular Spectroscopy, 118 (1) :18-39
1986

DOI: 10.1016/0022-2852(86)90220-1

143.

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

DOI: 10.1063/1.450944

142.

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

DOI: 10.1063/1.450944

141.

Bunker, Philip R.; Jensen, Per; Kraemer, Wolfgang P.; Beardsworth, R.
The potential surface of X~3B1 methylene (CH2) and the singlet-triplet splitting
The Journal of Chemical Physics, 85 (7) :3724-3731
1986

DOI: 10.1063/1.450944

140.

Vojt{í}k, Jan; Spirko, Vladim{í}r; Jensen, Per
Vibrational energies of H\(_{3}\)\(^{+}\) and Li\(_{3}\)\(^{+}\) based on the diatomics-in-molecules potentials
Collection of Czechoslovak Chemical Communications, 51 (10) :2057-2062
1986
Herausgeber: Institute of Organic Chemistry and Biochemistry AS CR, v.v.i.

DOI: 10.1135/cccc19862057

139.

Vojt{í}k, Jan; Spirko, Vladim{í}r; Jensen, Per
Vibrational energies of H\(_{3}\)\(^{+}\) and Li\(_{3}\)\(^{+}\) based on the diatomics-in-molecules potentials
Collection of Czechoslovak Chemical Communications, 51 (10) :2057-2062
1986
Herausgeber: Institute of Organic Chemistry and Biochemistry AS CR, v.v.i.

DOI: 10.1135/cccc19862057

138.

Vojtík, Jan; Spirko, Vladimír; Jensen, Per
Vibrational energies of H3+ and Li3+ based on the diatomics-in-molecules potentials
Collection of Czechoslovak Chemical Communications, 51 (10) :2057-2062
1986
Herausgeber: Institute of Organic Chemistry and Biochemistry AS CR, v.v.i.

DOI: 10.1135/cccc19862057

1985

137.

Holstein, K. J.; Fink, Ewald H.; Wildt, J{ü}rgen; Zabel, Friedhelm
A\verb=~=\(^{2}\)A' → X\verb=~=\(^{2}\)A'' emission spectrum of the HS\(_{2}\) radical
Chemical Physics Letters, 113 (1) :1-7
1985

DOI: 10.1016/0009-2614(85)85001-6

136.

Holstein, K. J.; Fink, Ewald H.; Wildt, J{ü}rgen; Zabel, Friedhelm
A\verb=~=\(^{2}\)A' → X\verb=~=\(^{2}\)A'' emission spectrum of the HS\(_{2}\) radical
Chemical Physics Letters, 113 (1) :1-7
1985

DOI: 10.1016/0009-2614(85)85001-6

135.

Holstein, K. J.; Fink, Ewald H.; Wildt, Jürgen; Zabel, Friedhelm
A~2A' → X~2A" emission spectrum of the HS2 radical
Chemical Physics Letters, 113 (1) :1-7
1985

DOI: 10.1016/0009-2614(85)85001-6

134.

Tausch, Michael W.
Aktivierungsenergie - was ist das?
Praxis der Naturwissenschaften (Chemie), 34 :33
1985

133.

Phillips, R.A.; Buenker, Robert J.; Beardsworth, R.; Bunker, Philip R.; Jensen, Per; Kraemer, Wolfgang P.
An ab initio study of the rotation-vibration energy levels of GeH\(_{2}\) in the a\verb=~=\(^{3}\)B\(_{1}\) state
Chemical Physics Letters, 118 (1) :60-63
1985

DOI: 10.1016/0009-2614(85)85266-0