ABSTRACT
Control panel waste generated from nuclear power plants is a new candidate for clearance under Japan's amended regulations. In the radioactivity evaluation, a simplified conversion factor for density and source location conditions has been used, assuming that it applies to unmixed materials such as metals. To investigate its applicability to control panels consisting of metal and organic materials, we examined the application of the conventional conversion factor by simulations of radiation measurements for a point source in a control panel.
ABSTRACT
We developed a path-planning system for radiation source identification devices using 4π gamma imaging. The estimated source location and activity were calculated by an integrated simulation model by using 4π gamma images at multiple measurement positions. Using these calculated values, a prediction model to estimate the probability of identification at the next measurement position was created by via random forest analysis. The path-planning system based on the prediction model was verified by integrated simulation and experiment for a 137Cs point source. The results showed that 137Cs point sources were identified using the few measurement positions suggested by the path-planning system.
Subject(s)
Diagnostic Imaging , Radiotherapy Planning, Computer-Assisted , Radioisotopes , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted/methodsABSTRACT
Pulse shape processing techniques have been used to improve the energy spectrum of the cadmium zinc telluride (CZT) detector, however, quantitative evaluation of the improvement, to determine whether it is acceptable to the related stakeholders, is required. In this study, the detection limit of net count in the full-energy absorption peak according to ISO 11929-1:2019 was selected to quantitatively evaluate the improvement of the characteristics of net count in the peak in the energy spectrum.