1-calculate the dose rate as the robot walk
then make a map for the path with least radiation 


2- we can define the radionuclides in eah area depends on the data collected from the energy spectroscopy 

3- the accumulated dose calculation with time of the robot be in the site 


4- gadolinium layer, acts as a n-gamma converter, we could know these gamma signals from neutrons 

5- The critical masses for fuel debris with various compositions are being calculated to evaluate the re-criticality risk level of each operation such as fragmentation,
 removal and storage of fuel debris. For the operations with higher risk levels, the detection system of subcriticality is developed as the safety net of the re-criticality countermeasure.
It is also important to validate R&D results before their application to the actual operations in Fukushima Daiichi NPP site. Therefore, a small reactor, so called "criticality assembly", 
is used to confirm the accuracy of critical mass calculations by measuring the critical mass of the simulated fuel debris, or to demonstrate countermeasure reliability by testing sensitivity 
of neutron detectors and effectiveness of neutron poison.