Estimation of radionuclide intakes by singular value decomposition

Hato, Shinji*; Kinase, Sakae   

It is significant to accurately estimate the intake quantity for the reliable internal exposure assessments. The intake quantity has been estimated by using least squares method. However, to conduct the least squares method, the number of radioactivity measurements must be more than the number of intakes. To remedy this restriction, this study suggests the estimation method using a singular value decomposition that is available regardless the relation of numbers between measurements and intakes. Moreover, this study introduces the procedure to calculate the intake quantity from the measurements with uncertainty.