TY CONF TI APPLICATION OF FAST EXPANSIONS TO STUDY THE STRESS STATE OF A RECTANGULAR PLATE ON AN ELASTIC BASE KW biharmonic equation KW deflection KW torsional and bending moments KW shear forces KW stress tensor components KW universal fast expansions KW high accuracy JO OPERATOR EQUATIONS AND SOME RELATED ISSUES IN APPLIED MATHEMATICS AU Chernyshov, A.D. AU Goryainov, V.V. AU Nikiforova, O.Y. PY 2026 PB FSBE Institution of Higher Education Voronezh State University of Forestry and Technologies named after G.F. Morozov