Issues of improving quality of contact wire Dilshod Nigmatullaevich Isamukhamedov, Daniyar Bakhtiyarovich Madrahimov, Rano Fazildzhanovna Atamukhamedova and Nigora Jakhongirovna Tairova E3S Web Conf., 216 (2020) 01154 Published online: 14 December 2020 DOI: 10.1051/e3sconf/202021601154