Inverse radiation modelling for plant characterisation

A requirement to actively manage radiation dose is often the biggest single constraint in activities associated with the operation and decommissioning of nuclear facilities. Often this management involves the minimisation of accrued dose for employees and contractors who work in the vicinity of the managed area. An important tool for evaluating the effectiveness of remediation of this dose is environmental modelling; however results are often inaccurate or misleading due to poor characterisation of the underlying source activity. In this paper we present a method for semi-automatically calculating source terms using an inverse modelling approach. This approach has been used as a basis for a new software package called N-Visage^tm which has been used to demonstrate the performance of the method in both controlled experiments and real-world applications.