s amiri department of medical physics and biomedical engineering, school of medicine, shiraz university of medical sciences, shiraz, iran mm movahedi department of medical physics and biomedical engineering, school of medicine, shiraz university of medical sciences, shiraz, iran k kazemi department of electrical and electronics engineering, shiraz university of technology, shiraz, iran h parsaei department of medical physics and biomedical engineering, school of medicine, shiraz university of medical sciences, shiraz, iran