TY JOUR TI INDUCTION LAMPS KW induction lamp KW electromagnetic field KW magnetic field KW induction coil KW magnetic ring (magnetic conductor) KW electric coil KW power coefficient JO Bulletin of KSAU AU Kungs, Y.A. AU Kovaleva, O.A. AU Kibardin, V.V. PY 2013 IS PB Krasnoyarsk State Agrarian University