4 papers
On Description of Dual Frames
Alan Kamuda, Sergiusz Kużel
One of a key problems in signal reconstruction process with the use of frames is to find a dual frame. Typically, a canonical dual frame is used. However, there are many applicatio…
Towards Generalized Riesz Systems Theory
Alan Kamuda, Sergiusz Kużel
Pseudo-Hermitian Hamiltonians have recently become a field of wide investigation. Originally, the Generalized Riesz Systems (GRS) have been introduced as an auxiliary tool in this…
On dual definite subspaces in Krein space
A. Kamuda, S. Kuzhel, V. Sudilovskaya
Extensions of dual definite subspaces to dual maximal definite ones are described. The concepts of dual quasi maximal subspaces and quasi basis are introduced and studied. The obta…
On -frames related to maximal definite subspaces
Alan Kamuda, Sergiusz Kużel
A definition of frames in Krein spaces is proposed which extends the concept of -frames defined by J.I. Giribet et al., J. Math. Anal. Appl. (2012), 122-137. Th…