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Variational integrators for electric circuits [article]

Sina Ober-Blöbaum, Molei Tao, Mulin Cheng, Houman Owhadi, Jerrold E. Marsden
2011 arXiv   pre-print
Dependent on the discretization, the intrinsic degeneracy of the system can be canceled for the discrete variational scheme.  ...  In this way, a variational integrator is constructed that gains several advantages compared to standard integration tools for circuits; in particular, a comparison to BDF methods (which are usually the  ...  Introduction Variational integrators have mainly been developed and used for a wide variety of mechanical systems. However, real-life systems are generally not of purely mechanical character.  ... 
arXiv:1103.1859v1 fatcat:qguddhjkonghzhjcrvv5tjblkm

Variational integrators for electric circuits

Sina Ober-Blöbaum, Molei Tao, Mulin Cheng, Houman Owhadi, Jerrold E. Marsden
2013 Journal of Computational Physics  
Dependent on the discretization, the intrinsic degeneracy of the system can be canceled for the discrete variational scheme.  ...  In this way, a variational integrator is constructed that gains several advantages compared to standard integration tools for circuits; in particular, a comparison to BDF methods (which are usually the  ...  Introduction Variational integrators have mainly been developed and used for a wide variety of mechanical systems. However, real-life systems are generally not of purely mechanical character.  ... 
doi:10.1016/j.jcp.2013.02.006 fatcat:4neyyxbi7vhefpnypfh5r5olee

Page 1250 of Mathematical Reviews Vol. 50, Issue 4 [page]

1975 Mathematical Reviews  
These algebra deformations are related to multiplier representations and manifold mappings of the corresponding Lie groups.  ...  The equation for radiative heat transfer, which is a nonlinear integral equation for the temperature, is solved by an iterative algorithm developed previously by the authors and suitable for inexact data  ... 

C++ implementations of numerical methods for solving differential-algebraic equations: design and optimization considerations

Christopher E. Kees, Cass T. Miller
1999 ACM Transactions on Mathematical Software  
The comparisons demonstrate that the majority of Cϩϩ's built-in support for OO programming has a negligible effect on performance, when used at sufficiently high levels, and provides flexible and extensible  ...  The codes were tested on a variety of problems using publicly available Fortran 77 and Cϩϩ compilers.  ...  Kanney for experimenting with early versions of DAE-TK in their work and participating in discussions on its design.  ... 
doi:10.1145/332242.334001 fatcat:ur45ifctgvfpdjpxe7dmzdf2we

Benchmarking stiff ode solvers for atmospheric chemistry problems II: Rosenbrock solvers

A. Sandu, J.G. Verwer, J.G. Blom, E.J. Spee, G.R. Carmichael, F.A. Potra
1997 Atmospheric Environment  
In the numerical simulation of atmospheric transport-chemistry processes, a major task is the integration of the stiff systems of ordinary differential equations describing the chemical transformations  ...  These tum out to be very well suited for our application when they are provided with highly efficient sparse matrix techniques to economize on the linear algebra.  ...  ., 1993) for different scenario's based on the CBM-IV mechanism.  ... 
doi:10.1016/s1352-2310(97)83212-8 fatcat:gov5e3wj2bfldcf5qth4az3sv4

Dynamical population synthesis: constructing the stellar single and binary contents of galactic field populations

Michael Marks, Pavel Kroupa
2011 Monthly notices of the Royal Astronomical Society  
On cluster dissolution the population enters the galactic field with these characteristics.  ...  This gives rise to integrated galactic field binary distribution functions (IGBDFs) resembling a galactic field's stellar content (Dynamical Population Synthesis).  ...  Menten for useful suggestions. We thank D. Raghavan for discussions and help with their data.  ... 
doi:10.1111/j.1365-2966.2011.19519.x fatcat:j44yeyiru5h3jjxbvjmctpgwiy

Numerical Analysis 2000

Christopher Baker, Manchester, Giovanni Monegato, Turin, John Pryce, Shrivenham, Guido Vanden Berghe, Gent
2000 Journal of Computational and Applied Mathematics  
Numerical methods for initial-value problems in ordinary di erential equations fall naturally into two classes: those which use one starting value at each step (one-step methods) and those which are based  ...  This volume contains contributions in the area of di erential equations and integral equations.  ...  . • Delay di erential equations also arise in mechanical systems, and the paper by John Norbury and Eddie Wilson relates to a form of constrained problem that has application to the control of a motor.  ... 
doi:10.1016/s0377-0427(00)00454-4 fatcat:o3rxyb3745d6hebfybjmirgppe

Nonlinear MPC and MHE for Mechanical Multi-Body Systems with Application to Fast Tethered Airplanes

Sébastien Gros, Mario Zanon, Milan Vukov, Moritz Diehl
2012 IFAC Proceedings Volumes  
The symbolic complexity of the model equations for multi-body mechanical systems can often be dramatically reduced by using representations based on non-minimal coordinates, which result in index-3 differential-algebraic  ...  times that can be achieved on a tethered airplane system using code generation.  ...  The system dynamics are discretized over the shooting intervals via the BDF integration method.  ... 
doi:10.3182/20120823-5-nl-3013.00061 fatcat:r7szfid2pnctjdxkjgxb2saf2a

Zamolodchikov's tetrahedron equation and hidden structure of quantum groups

Vladimir V Bazhanov, Sergey M Sergeev
2006 Journal of Physics A: Mathematical and General  
Its solutions define integrable three-dimensional lattice models of statistical mechanics and quantum field theory.  ...  Obviously, any such three-dimensional model can be viewed as a two-dimensional integrable model on a square lattice, where the additional third dimension is treated as an internal degree of freedom.  ...  One the authors (VVB) thanks Alexander Zamolodchikov and Vladimir Kazakov for interesting discussions and their hospitality at the ENS, Paris, where some parts of this work were completed.  ... 
doi:10.1088/0305-4470/39/13/009 fatcat:edmj4wevfbgwpgukvnnnz3bli4

On-Line Symbolic Constraint Embedding for Simulation of Hybrid Dynamical Systems

R. Brent Gillespie, Volkan Patoglu, Islam I. Hussein, E. R. Westervelt
2005 Multibody system dynamics  
Constraint-embedding undertaken on-the-fly enables the simulation of systems with an ODE solver for which constraints are not known prior to simulation start or for which the enumeration of all constraint  ...  We apply nomenclature developed for hybrid dynamical systems to describe the system with changing constraints and to distinguish the roles of the forward dynamics solver, a collision detector, and an impact  ...  We have also implemented a fourth order BDF formula for simulation of formulation using DAEs.  ... 
doi:10.1007/s11044-005-0269-0 fatcat:z35tvctrkze5xjdazgj62tnnmi

Specification Analysis of Affine Term Structure Models

Qiang Dai, Kenneth J. Singleton
1998 Social Science Research Network  
Specializing to three-factor ATSMs, our analysis suggests, based on theoretical considerations and empirical evidence, that some subfamilies of ATSMs are better suited than others to explaining historical  ...  A notable feature of the t-ratios for the individual scores is that they are often large for models A 1~3 ! BDFS and A 2~3 ! Chen for all three groups A, ⌿, and t.  ...  Finally, the BDFS model constrains k rv ϭ 0 so that v cannot affect the drift of r.  ... 
doi:10.2139/ssrn.139422 fatcat:jghsaajxjze77kf3nn5dgyr5bu

Specification Analysis of Affine Term Structure Models

Qiang Dai, Kenneth J. Singleton
2000 Journal of Finance  
Specializing to three-factor ATSMs, our analysis suggests, based on theoretical considerations and empirical evidence, that some subfamilies of ATSMs are better suited than others to explaining historical  ...  A notable feature of the t-ratios for the individual scores is that they are often large for models A 1~3 ! BDFS and A 2~3 ! Chen for all three groups A, ⌿, and t.  ...  Finally, the BDFS model constrains k rv ϭ 0 so that v cannot affect the drift of r.  ... 
doi:10.1111/0022-1082.00278 fatcat:ixrmtk4n5jegrbjl3ykptlyk7a

A numerical study for global atmospheric transport–chemistry problems

E.J. Spee, J.G. Verwer, P.M. de Zeeuw, J.G. Blom, W. Hundsdorfer
1998 Mathematics and Computers in Simulation  
Use of fast, tailored numerical algorithms implemented on the most advanced computer systems is then needed for making real progress.  ...  This paper is devoted to a performance study of algorithms developed for solving global atmospheric transport-chemistry problems.  ...  Recall that for the gridvectorization we group points ( i ; j ) on the globe in clusters of length 128. But now we have p processors available instead of only one.  ... 
doi:10.1016/s0378-4754(98)00155-4 fatcat:k5zgjpouxne4ffqdw5ejfyrfym

Key Techniques for interactive Virtual Garment Simulation [article]

Pascal Volino, Nadia Magnenat-Thalmann, Bernhard Thomaszewski, Markus Wacker
2005 Eurographics State of the Art Reports  
Virtual garment design and simulation involves a combination of a large range of techniques, involving mechanical simulation, collision detection, and user interface techniques for creating garments.  ...  an extensive review of the evolution of these techniques made in the last decade to bring virtual garments to the reach of computer applications not only aimed at graphics, but also at CAD techniques for  ...  This requires advanced methods for efficiently detecting the geometrical contacts constraining the behavior of the cloth, and to integrate them in the mechanical model (collision detection and response  ... 
doi:10.2312/egt.20051053 fatcat:yfpy6t5y6rhtvjwedgldfr3l7i

Energetics of Ortho-7 (Oxime Drug) Translocation through the Active-Site Gorge of Tabun Conjugated Acetylcholinesterase

Vivek Sinha, Bishwajit Ganguly, Tusar Bandyopadhyay, Emad Tajkhorshid
2012 PLoS ONE  
PLoS ONE 7(7): e40188.  ...  The potential locates the binding sites and barriers for the drug to translocate inside the gorge.  ...  Amit Das for several useful discussions. TB is grateful to Prof. R. Chelli for kindly providing one necessary software customized here to calculate free energy profiles. TB is also thankful to Prof.  ... 
doi:10.1371/journal.pone.0040188 pmid:22808117 pmcid:PMC3394793 fatcat:htjdwockqfemngfdksmhx3howq
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