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A variant of the complex Liouville-Green approximation theorem

Renato Spigler, Marco Vianello (2000)

Archivum Mathematicum

We propose a variant of the classical Liouville-Green approximation theorem for linear complex differential equations of the second order. We obtain rigorous error bounds for the asymptotics at infinity, in the spirit of F. W. J. Olver’s formulation, by using rather arbitrary ξ -progressive paths. This approach can provide higher flexibility in practical applications of the method.

A variational approach to implicit ODEs and differential inclusions

Sergio Amat, Pablo Pedregal (2009)

ESAIM: Control, Optimisation and Calculus of Variations

An alternative approach for the analysis and the numerical approximation of ODEs, using a variational framework, is presented. It is based on the natural and elementary idea of minimizing the residual of the differential equation measured in a usual Lp norm. Typical existence results for Cauchy problems can thus be recovered, and finer sets of assumptions for existence are made explicit. We treat, in particular, the cases of an explicit ODE and a differential inclusion. This approach also allows...

A verified method for solving piecewise smooth initial value problems

Ekaterina Auer, Stefan Kiel, Andreas Rauh (2013)

International Journal of Applied Mathematics and Computer Science

In many applications, there is a need to choose mathematical models that depend on non-smooth functions. The task of simulation becomes especially difficult if such functions appear on the right-hand side of an initial value problem. Moreover, solution processes from usual numerics are sensitive to roundoff errors so that verified analysis might be more useful if a guarantee of correctness is required or if the system model is influenced by uncertainty. In this paper, we provide a short overview...

A version of non-Hamiltonian Liouville equation

Celina Rom (2014)

Discussiones Mathematicae, Differential Inclusions, Control and Optimization

In this paper we give a version of the theorem on local integral invariants of systems of ordinary differential equations. We give, as an immediate conclusion of this theorem, a condition which guarantees existence of an invariant measure of local dynamical systems. Results of this type lead to the Liouville equation and have been frequently proved under various assumptions. Our method of the proof is simpler and more direct.

A viability result for nonconvex semilinear functional differential inclusions

Vasile Lupulescu, Mihai Necula (2005)

Discussiones Mathematicae, Differential Inclusions, Control and Optimization

We establish some sufficient conditions in order that a given locally closed subset of a separable Banach space be a viable domain for a semilinear functional differential inclusion, using a tangency condition involving a semigroup generated by a linear operator.

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