English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Some special Hilbert spaces are introduced to present the class ofinfinitesimal operators with complete minimal non-basis family of eigenvectors.The discrete Hardy inequality plays an important role in the proposed approach.The construction complement the results of G.Q.~Xu et al.~\cite{Xu} (2005) andH.~Zwart~\cite{Zwart} (2010) on the Riesz basis property of eigenvectors(eigenspaces) of infinitesimal operators. Our results are extended to the caseof operators on some Banach spaces.

Hardy inequality and the construction of infinitesimal operators with non-basis family of eigenvectors