Abstract Segmentation is one of the vital procedures in medical image processing. The results of none accurate segmentation may lead to a none accurate diagnosis. To assess the segmentation results there are common used criteria such as Sensitivity, Specificity and Accuracy. This paper discusses of disadvantages of the mentioned criteria in assessment the tumor segmentation on MRI images.  

Abstract Radon ( 222 Rn) and its decay products are the dominating contributors to the total collective radiation exposure of world’s population. Besides that, the exposure to radon and its decay products have been identified as the second significant cause of lung cancer after smoking (WHO 2009). The value of indoor and outdoor exposure can be varied and the study of indoor value is important due to its apparent health implications in particular dwellings. Radon and its decay products are present in the indoor air since their parent nuclei radium is present in the soil, natural construction and building materials. The Concentrations of radon decay products were measured using an alpha-spectroscopy with surface barrier detector during one year in radiation laboratory, physics department, faculty of science, minia University, at least one measure per week. The mean activity concentrations of 218 Po, 214 Pb and 214 Bi over one year are founded to be 6.6 ± 0.64, 5.3 ± 0.5 and 4±0.42 Bq/m 3  respectively. Radon EEC and The annual effective dose is calculated using UNSCEAR model and the result is within the national indoor recommended limit. The annual effective dose is 0.33 mSv y −1 .