Mathematical Inequalities & Applications · Volume 24, Issue 2 Approximate ω-orthogonality and ω-derivation 24-32 Pages 463-476 DOI 10.7153/mia-2021-24-32 Downloads Short PDF Full PDF PNG Authors Maryam Amyari Marzieh Moradian Khibary Keywords Hilbert space numerical radius approximate ω-orthogonality ω-derivation Subject classes 47A12 46B20 46C05