Results 21 to 30 of about 7,875,654 (350)
A Reduction Method for Higher Order Variational Equations of Hamiltonian Systems [PDF]
arXiv.org, 2012 . Let k be a differential field and let [A] : Y ′ = AY be a linear differential system where A ∈ Mat(n , k). We say that A is in a reduced form if A ∈ g(k̄) where g is the Lie algebra of [A] and k̄ denotes the algebraic closure of k. We owe the existence
Ainhoa Aparicio-Monforte +1 more
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Variational Time Integrators in Computational Solid Mechanics [PDF]
, 2003 This thesis develops the theory and implementation of variational integrators for computational solid mechanics problems, and to some extent, for fluid mechanics problems as well.
Lew, Adrián José
core +1 more source
A minimax approach for the study of systems of variational equations and related Galerkin schemes
Journal of Computational and Applied Mathematics, 2019 The aim of this work is to analyze the existence of a solution for a quite general variational inequalities system, which includes those appearing in the theory of mixed variational equations, the so-called Babuska–Brezzi theory. It is done by means of a
A. Guillem, M. R. Galán
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Modified equations for variational integrators [PDF]
Numerische Mathematik, 2017 It is well-known that if a symplectic integrator is applied to a Hamiltonian system, then the modified equation, whose solutions interpolate the numerical solutions, is again Hamiltonian. We investigate this property from the variational side. We present a technique to construct a Lagrangian for the modified equation from the discrete Lagrangian of a ...
openaire +2 more sources
Variational Methods for Nonsmooth Mechanics [PDF]
, 2003 In this thesis we investigate nonsmooth classical and continuum mechanics and its discretizations by means of variational numerical and geometric methods.
Fetecau, Razvan Constantin
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Numerical integration of variational equations [PDF]
Mathematics of Computation, 1967 Introduction. In solving a system of algebraic equations it is well known that the problem is much simpler if the equations are linear. In solving a system of differential equations, one usually does not really care if the equations are linear or not, even though a simplification is possible in the linear case; namely by observing that in a predictor ...
Riley, James D. +2 more
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Symbolic Computation of Polynomial Conserved Densities, Generalized Symmetries, and Recursion Operators for Nonlinear Differential-Difference Equations [PDF]
, 2004 Algorithms for the symbolic computation of polynomial conserved densities, fluxes, generalized symmetries, and recursion operators for systems of nonlinear differential-difference equations are presented. In the algorithms we use discrete versions of the
Jan A. S +15 more
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The Deep Ritz Method: A Deep Learning-Based Numerical Algorithm for Solving Variational Problems [PDF]
Communications in Mathematics and Statistics, 2017 We propose a deep learning-based method, the Deep Ritz Method, for numerically solving variational problems, particularly the ones that arise from partial differential equations. The Deep Ritz Method is naturally nonlinear, naturally adaptive and has the
E. Weinan, Ting Yu
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GRACETOOLS—GRACE Gravity Field Recovery Tools
Geosciences, 2018 This paper introduces GRACETOOLS, the first open source gravity field recovery tool using GRACE type satellite observations. Our aim is to initiate an open source GRACE data analysis platform, where the existing algorithms and codes for working with ...
Neda Darbeheshti +4 more
doaj +1 more source
Analytic approximate solutions for some nonlinear Parabolic dynamical wave equations
Journal of Taibah University for Science, 2020 In this paper, modified variational iteration algorithm-II is investigated for finding approximate solutions of nonlinear Parabolic equations. Comparisons of the MVIA-II with trigonometric B-spline collocation method, variational iteration method ...
Hijaz Ahmad +3 more
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