TY CONF TI RELATIONS BETWEEN COMPLETE MODULI OF SMOOTHNESS IN DIFFERENT METRICS KW mixed metric KW complete moduli of smoothness JO OPERATOR EQUATIONS AND SOME RELATED ISSUES IN APPLIED MATHEMATICS AU Simonov, B.V. AU Simonova, I.E. PY 2026 PB FSBE Institution of Higher Education Voronezh State University of Forestry and Technologies named after G.F. Morozov