1. Department of Biomedical Sciences and Biomedical Engineering, Faculty of Medicine, Prince of Songkla University Songkhla, Songkhla, Thailand
2. Department of Electrical Engineering, Faculty of Engineering, Prince of Songkla University, Songkhla, Thailand
3. Department of Surgery, Division of Neurosurgery, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand,