1. Nuclear Science and Technology Development Center, National Tsing Hua University, Hsinchu 300044, Taiwan
2. Department of Heavy Particles and Radiation Oncology, Taipei Veterans General Hospital, Taipei 11217, Taiwan
3. Department of Medical Imaging and Radiological Technology, Yuanpei University of Medical Technology, Hsinchu 30015, Taiwan
4. Institute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu 300044, Taiwan