Perfecting evaluation methods of energy equipment technical condition and resource based on electromagnetic-acoustic effectM.G. Bashirov, N.N. Luneva, I.G. Khusnutdinova, E.M. Bashirova, N.M. Zakharov and R.R. GazievE3S Web Conf., 124 (2019) 05034DOI: https://doi.org/10.1051/e3sconf/201912405034