Spectral properties of an operator polynomial with coefficients in a Banach algebra

Author(s):  
Anatoly Baskakov ◽  
Ilya Krishtal
1969 ◽  
Vol 66 (2) ◽  
pp. 265-274 ◽  
Author(s):  
M. A. Kaashoek ◽  
T. T. West

A monothetic semigroup is a topological semigroup with jointly continuous multiplication which contains a dense cyclic subsemigroup. These semi-groups arise in a natural way in the study of semi-algebras. In (4) we showed that a compact monothetic semigroup in a Banach algebra can be characterized in terms of the spectral properties of a generating element. In this paper these spectral theorems are linked with the well-known structure theory of compact semigroups.


1991 ◽  
Vol 33 (1) ◽  
pp. 11-20 ◽  
Author(s):  
J. J. Grobler ◽  
H. Raubenheimer

Let A be a Banach algebra with unit 1 and let B be a Banach algebra which is a subalgebra of A and which contains 1. In [5]Barnes gave sufficient conditions for B to be inverse closed in A. In this paper we consider single elements and study the question of how the spectrum relative to B of an element in B relates to the spectrum of the element relative to A.


2020 ◽  
Vol 2020 (48) ◽  
pp. 17-24
Author(s):  
I.M. Javorskyj ◽  
◽  
R.M. Yuzefovych ◽  
P.R. Kurapov ◽  
◽  
...  

The correlation and spectral properties of a multicomponent narrowband periodical non-stationary random signal (PNRS) and its Hilbert transformation are considered. It is shown that multicomponent narrowband PNRS differ from the monocomponent signal. This difference is caused by correlation of the quadratures for the different carrier harmonics. Such features of the analytic signal must be taken into account when we use the Hilbert transform for the analysis of real time series.


2015 ◽  
Vol 60 (04) ◽  
pp. 356-361 ◽  
Author(s):  
A. Tolochko ◽  
◽  
P. Teselko ◽  
A. Lyashchova ◽  
D. Fedorenko ◽  
...  

Filomat ◽  
2019 ◽  
Vol 33 (8) ◽  
pp. 2249-2255
Author(s):  
Huanyin Chen ◽  
Marjan Abdolyousefi

It is well known that for an associative ring R, if ab has g-Drazin inverse then ba has g-Drazin inverse. In this case, (ba)d = b((ab)d)2a. This formula is so-called Cline?s formula for g-Drazin inverse, which plays an elementary role in matrix and operator theory. In this paper, we generalize Cline?s formula to the wider case. In particular, as applications, we obtain new common spectral properties of bounded linear operators.


1980 ◽  
Vol 45 (8) ◽  
pp. 2247-2253 ◽  
Author(s):  
Václav Konečný ◽  
Štefan Varkonda ◽  
Vojtech Kubala

Syntheses of O-ethyl-S-propyl-O-(1-alkyl, phenyl-5-chloro, alkoxy-6-oxo-1H-pyridazine-4-yl) esters of dithiophosphoric acid are described. The compounds were investigated for their IR and UV spectra and for their contact and system activities as insecticides, acaricides, ovicides, fungicides and herbicides. Some of the compounds proved efficient acaricides; compound VIII also had an insecticide activity.


Sign in / Sign up

Export Citation Format

Share Document