1. Department of Radiation Oncology, University of Florida, FL, USA.
2. Department of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul, Korea.
3. Research Institute of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul, Korea.
4. Department of Radiation Oncology, Konkuk University Medical Center, Seoul, Korea.
5. Department of Radiology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
6. Department of Radiation Oncology, Ajou University School of Medicine, Suwon, Korea.