RETRACTED: Modernization of existing infrastructure, heat supply systems Parviz Khujaev, Zokhidjon Abdulkhaev, Shohkzodbek Numonjonov, Nematulla Karimov and Kambarali Akhunov E3S Web Conf., 538 (2024) 01010 Published online: 14 June 2024 DOI: 10.1051/e3sconf/202453801010