Reconfigurable Intelligent Surfaces: A Hardware-Centric Review of Structures, Implementation, Evaluation, and Integration With UAV and Machine Learning. - Binh Nguyen Thai; Thinh Nguyen Tien; Khanh Doan Minh; Manh Nguyen Tien; Ta Thi Kim Hue; Nguyen Xuan Quyen (IEEE Access, 2025)