Previous Page 2

Displaying 21 – 31 of 31

Showing per page

Optimal, adaptive and single state feedback control for a 3D chaotic system with golden proportion equilibria

Hassan Saberi Nik, Ping He, Sayyed Taha Talebian (2014)

Kybernetika

In this paper, the problems on purposefully controlling chaos for a three-dimensional quadratic continuous autonomous chaotic system, namely the chaotic Pehlivan-Uyaroglu system are investigated. The chaotic system, has three equilibrium points and more interestingly the equilibrium points have golden proportion values, which can generate single folded attractor. We developed an optimal control design, in order to stabilize the unstable equilibrium points of this system. Furthermore, we propose...

Relaxation of quasilinear elliptic systems via A-quasiconvex envelopes

Uldis Raitums (2002)

ESAIM: Control, Optimisation and Calculus of Variations

We consider the weak closure W Z of the set Z of all feasible pairs (solution, flow) of the family of potential elliptic systems where Ω 𝐑 n is a bounded Lipschitz domain, F s are strictly convex smooth functions with quadratic growth and S = { σ m e a s u r a b l e σ s ( x ) = 0 or 1 , s = 1 , , s 0 , σ 1 ( x ) + + σ s 0 ( x ) = 1 } . We show that W Z is the zero level set for an integral functional with the integrand Q being the 𝐀 -quasiconvex envelope for a certain function and the operator 𝐀 = ( curl,div ) m . If the functions F s are isotropic, then on the characteristic cone Λ (defined by the operator 𝐀 ) Q coincides...

Relaxation of Quasilinear Elliptic Systems via A-quasiconvex Envelopes

Uldis Raitums (2010)

ESAIM: Control, Optimisation and Calculus of Variations

We consider the weak closure WZ of the set Z of all feasible pairs (solution, flow) of the family of potential elliptic systems div s = 1 s 0 σ s ( x ) F s ' ( u ( x ) + g ( x ) ) - f ( x ) = 0 in Ω , u = ( u 1 , , u m ) H 0 1 ( Ω ; 𝐑 m ) , σ = ( σ 1 , , σ s 0 ) S , where Ω ⊂ Rn is a bounded Lipschitz domain, Fs are strictly convex smooth functions with quadratic growth and S = { σ m e a s u r a b l e σ s ( x ) = 0 or 1 , s = 1 , , s 0 , σ 1 ( x ) + + σ s 0 ( x ) = 1 } . We show that WZ is the zero level set for an integral functional with the integrand Q being the A-quasiconvex envelope for a certain function and the operator A = (curl,div)m. If the functions Fs are isotropic, then on the characteristic cone...

Resilient asynchronous primal Schur method

Guillaume Gbikpi-Benissan, Frédéric Magoulès (2022)

Applications of Mathematics

This paper introduces the application of asynchronous iterations theory within the framework of the primal Schur domain decomposition method. A suitable relaxation scheme is designed, whose asynchronous convergence is established under classical spectral radius conditions. For the usual case where local Schur complement matrices are not constructed, suitable splittings based only on explicitly generated matrices are provided. Numerical experiments are conducted on a supercomputer for both Poisson's...

Signal reconstruction from given phase of the Fourier transform using Fejér monotone methods

Dieter Schott (2000)

Discussiones Mathematicae, Differential Inclusions, Control and Optimization

The aim is to reconstruct a signal function x ∈ L₂ if the phase of the Fourier transform [x̂] and some additional a-priori information of convex type are known. The problem can be described as a convex feasibility problem. We solve this problem by different Fejér monotone iterative methods comparing the results and discussing the choice of relaxation parameters. Since the a-priori information is partly related to the spectral space the Fourier transform and its inverse have to be applied in each...

Currently displaying 21 – 31 of 31

Previous Page 2