- Tytuł:
- Ingham-Type Inequalities and Riesz Bases of Divided Differences
- Autorzy:
-
Avdonin, S.
Moran, W. - Powiązania:
- https://bibliotekanauki.pl/articles/908080.pdf
- Data publikacji:
- 2001
- Wydawca:
- Uniwersytet Zielonogórski. Oficyna Wydawnicza
- Tematy:
-
bazy Riesza
sterowanie jednoczesne
simultaneous controllability
string equation
beam equation
Riesz bases
divided differences - Opis:
- We study linear combinations of exponentials e^{i lambda_n t}, lambda_n in Lambda in the case where the distance between some points lambda_n tends to zero. We suppose that the sequence Lambda is a finite union of uniformly discrete sequences. In (Avdonin and Ivanov, 2001), necessary and sufficient conditions were given for the family of divided differences of exponentials to form a Riesz basis in space L^2 (0,T). Here we prove that if the upper uniform density of Lambda is less than T/(2 pi), the family of divided differences can be extended to a Riesz basis in L^2 (0,T) by adjoining to {e^{i lambda_n t} } a suitable collection of exponentials. Likewise, if the lower uniform density is greater than T/(2 pi), the family of divided differences can be made into a Riesz basis by removing from {e^{i lambda_n t} } a suitable collection of functions e^{i lambda_n t}. Applications of these results to problems of simultaneous control of elastic strings and beams are given.
- Źródło:
-
International Journal of Applied Mathematics and Computer Science; 2001, 11, 4; 803-820
1641-876X
2083-8492 - Pojawia się w:
- International Journal of Applied Mathematics and Computer Science
- Dostawca treści:
- Biblioteka Nauki