Khanh Nguyen Gia 2025. Design and Optimization Framework for High-Efficiency Air Filtration Systems in Portable Respiratory Ventilators . Applied Science, Engineering and Management Bulletin [ASEMB]. 2, 03(July-Sep) (Sep. 2025), 69–75. DOI:https://doi.org/10.69889/asemb.v2i03(July-Sep).43.