Borislav Radkov Draganov

Borislav Radkov Draganov is a Professor of Mathematical Analysis at the Faculty of Mathematics and Informatics, Sofia University St. Kliment Ohridski. His research focuses on approximation theory, harmonic analysis, and operator theory.

Key research areas include:

• Trigonometric polynomial approximation
• Smoothness moduli and K-functionals
• Weighted approximation in function spaces
• Converse inequalities and saturation classes
• Sampling operators and multivariate approximation

His recent publications (2023-2025) analyze Voronovskaya estimates for convolution operators, saturation classes for generalized exponential sampling operators, and convergence rates in variable exponent Lebesgue spaces. Collaborators include Tuncer Acar and I. Gadjev.

He has extensively studied Peetre K-functionals, Bernstein-type operators, and Szasz-Mirakjan operators over two decades, establishing precise equivalence relations and Jackson-type inequalities in both homogeneous Banach spaces and weighted Lp spaces.