Analysis of System Operation Optimization In Steam Power Plants with the Lagrange Method - Aripriharta, Aripriharta; Husain, Rafli Amirul; Sujito, Sujito; Faiz, Mohamad Rodhi; Prasetyo, Muchamad Wahyu; Kusumawardana, Arya; Gumilar, Langlang; Habibi, Muhammad Afnan (Jurnal Ecotipe (Electronic Control Telecommunication Information and Power Engineering), 2024)