TY JOUR TI ASSESSMENT OF THE OPERATING COST OF UNMANNED AGRICULTURAL UNITS KW unmanned mobile vehicles KW conceptual model of unmanned mobile vehicles KW efficiency mark; operating cost JO Vestnik of Kazan State Agrarian University AU Starostin, I.A. AU Davydova, S.. AU YEin, A.. AU Degtyareva, E.D. PY 2024 IS 19 PB Kazan state agrarian University