Zobrazeno 1 - 10
of 48
pro vyhledávání: '"René Lamour"'
Autor:
René Lamour, Diana Estévez Schwarz
The recently developed new algorithm for computing consistent initial values and Taylor coefficients for DAEs using projector-based constrained optimization opens new possibilities to apply Taylor series integration methods. In this paper, we show ho
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b61516070644d898c0873d9a063a2289
http://edoc.hu-berlin.de/18452/27271
http://edoc.hu-berlin.de/18452/27271
Publikováno v:
Progress in Differential-Algebraic Equations II ISBN: 9783030539047
One of the benchmarks for higher-index DAEs is the so-called robotic arm, which results from a tracking problem in robotics. Testing this benchmark, we became aware of the singularities that appear and started to analyze them thoroughly. To our knowl
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::074e7ecfd31f6e378c770d64703a39ca
https://doi.org/10.1007/978-3-030-53905-4_14
https://doi.org/10.1007/978-3-030-53905-4_14
Autor:
René Lamour, Diana Estévez Schwarz
Publikováno v:
Numerical Algorithms. 78:355-377
This article describes a new algorithm for the computation of consistent initial values for differential-algebraic equations (DAEs). The main idea is to formulate the task as a constrained optimization problem in which, for the differentiated compone
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::ff72fe0fbd0214be3c3f49bea8c3ef8f
https://doi.org/10.1007/s11075-017-0379-9
https://doi.org/10.1007/s11075-017-0379-9
Autor:
Diana Estévez Schwarz, René Lamour
Publikováno v:
Journal of Computational and Applied Mathematics. 387:112486
InitDAE is a prototype written in Python that computes consistent initial values of differential–algebraic equations (DAE), determines their index and a related condition number that permits the diagnosis of singularities. The algorithm for the con
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::161c484b7fedcc2900af7826817b4191
https://doi.org/10.1016/j.cam.2019.112486
https://doi.org/10.1016/j.cam.2019.112486
Autor:
René Lamour, Diana Estévez Schwarz
Publikováno v:
Numerical Algorithms. 73:535-565
For higher index differential-algebraic equations (DAEs) some components of the solution depend on derivatives of the right-hand side. In this context, two main results are pointed out here. On the one hand, a description of the different types of un
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::14929a51dc6fde7557f1c437db8e2c0b
https://doi.org/10.1007/s11075-016-0107-x
https://doi.org/10.1007/s11075-016-0107-x
Autor:
René Lamour, Diana Estévez Schwarz
Publikováno v:
Numerical Algorithms. 70:777-805
The reliability of numerical results provided by conventional numerical integration methods for ODEs or DAEs depends on the properties of the problem. In particular, since the solution may not be unique at singular points, arbitrary solutions may be
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::baa37e28a14cd0489021d3c0150037fb
https://doi.org/10.1007/s11075-015-9973-x
https://doi.org/10.1007/s11075-015-9973-x
Index-analysis for a method of lines discretising multirate partial differential algebraic equations
In radio frequency applications, electric circuits generate signals, which are amplitude modulated and/or frequency modulated. A mathematical modelling yields typically systems of differential algebraic equations (DAEs). A multivariate signal model t
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e247ef2963996fcca94749d9d37c3055
http://arxiv.org/abs/1707.08201
http://arxiv.org/abs/1707.08201
Autor:
René Lamour, Diana Estévez Schwarz
Publikováno v:
Modeling, Simulation and Optimization of Complex Processes HPSC 2015 ISBN: 9783319671673
The quality of numerical simulations of DAE models depends on basic assumptions that exclude singularities. In practice, most algorithms used in simulation tools do not check the assumed properties of the DAE. Consequently, since the solution may not
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::edcf1a9d9832853c991bf91c53f8a16c
https://doi.org/10.1007/978-3-319-67168-0_8
https://doi.org/10.1007/978-3-319-67168-0_8
Autor:
Diana Estévez Schwarz, René Lamour
Publikováno v:
Numerical Algorithms. 69:667-691
At a singular point of a DAE, the IVP fails to have a unique solution. Hence, numerical integration methods cannot provide reasonable results. Unfortunately, common error control strategies do not always detect these circumstances and arbitrary solut
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::2e8cc1760123598b3f95bd8d1049fe01
https://doi.org/10.1007/s11075-014-9919-8
https://doi.org/10.1007/s11075-014-9919-8
Autor:
René Lamour, Diana Estévez Schwarz
Publikováno v:
Journal of Computational and Applied Mathematics. 262:62-72
Automatic (or Algorithmic) Differentiation (AD) opens new possibilities to analyze and solve DAEs by projector based methods. In this paper, we present a new approach to compute consistent initial values and integrate DAEs up to index two, considerin
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::5a1d6881260687b3d7dba8045d133bd7
https://doi.org/10.1016/j.cam.2013.09.018
https://doi.org/10.1016/j.cam.2013.09.018