Publication detail
Perturbation of nonnegative time scale quadratic functionals
HILSCHER, R. RŮŽIČKOVÁ, V.
Czech title
Perturbace nezáporných kvadratických funkcionálů na time scales.
English title
Perturbation of nonnegative time scale quadratic functionals
Type
conference paper
Language
en
Original abstract
In this paper we consider a bounded time scale T=[a,b] , a quadratic functional F(x,u) defined over such time scale, and its perturbation G(x,u)=F(x,u)+\alpha\,|x(a)|2 , where the endpoints of F are zero, while the initial endpoint x(a) of G can vary and x(b) is zero. It is known that there is no restriction on x(a) in G when studying the positivity of these functionals. We prove that, when studying the nonnegativity, the initial state x(a) in G must be restricted to a certain subspace, which is the kernel of a specific conjoined basis of the associated time scale symplectic system. This result generalizes a known discrete-time special case, but it is new for the corresponding continuous-time case. We provide several examples which illustrate the theory.
Czech abstract
V tomto článku uvažujeme time scale T=[a,b] , kvadratický functional F(x,u), definovaný na této množině, a jeho perturbaci G(x,u)=F(x,u)+\alpha\,|x(a)|2 , kde F má nulové konce, počáteční konec x(a) u G se mění a x(b) je nula. Je známo, že v případě pozitivity není omezení na x(a) u G. Dokážeme, že v případě nezápornosti, počáteční hodnota x(a) u G musí být omezená na jistý podprostor, který je jádrem specifické konjugované báze asociovaného symplektického systému na time scale. Tento výsledek zobecňuje známý speciální diskrétní případ, a je nový pro odpovídající spojitý případ. Uvedeme několik příkladů ilustrujících teorii.
English abstract
In this paper we consider a bounded time scale T=[a,b] , a quadratic functional F(x,u) defined over such time scale, and its perturbation G(x,u)=F(x,u)+\alpha\,|x(a)|2 , where the endpoints of F are zero, while the initial endpoint x(a) of G can vary and x(b) is zero. It is known that there is no restriction on x(a) in G when studying the positivity of these functionals. We prove that, when studying the nonnegativity, the initial state x(a) in G must be restricted to a certain subspace, which is the kernel of a specific conjoined basis of the associated time scale symplectic system. This result generalizes a known discrete-time special case, but it is new for the corresponding continuous-time case. We provide several examples which illustrate the theory.
Keywords in English
Quadratic functional, Nonnegativity, Positivity, Time scale, Time scale symplectic system, Hamiltonian system
Released
01.05.2007
ISBN
978-981-270-643-0
Book
DIFFERENCE EQUATIONS, SPECIAL FUNCTIONS AND ORTHOGONAL POLYNOMIALS Proceedings of the International Conference
Pages from–to
266–275
Pages count
10
BIBTEX
@inproceedings{BUT20211,
author="Roman Šimon {Hilscher} and Viera {Štoudková Růžičková},
title="Perturbation of nonnegative time scale quadratic functionals",
booktitle="DIFFERENCE EQUATIONS, SPECIAL FUNCTIONS AND ORTHOGONAL POLYNOMIALS Proceedings of the International Conference",
year="2007",
month="May",
pages="266--275",
isbn="978-981-270-643-0"
}