Karim, Maryam Ali, Maher Yahya Salloom, and Yasar N. Lafta. “Experimental Optimization of PLC-Integrated Multi-Loop PID Control for a Three-Level Electro-Hydraulic Elevator Using PSO and Cheetah Optimizer”. Engineering, Technology & Applied Science Research 16, no. 2 (April 4, 2026): 33836–33853. Accessed April 17, 2026. https://mail.etasr.com/index.php/ETASR/article/view/17143.