Category 1: Safety and risk studies from social, environmental and economic aspects of nuclear energy. 

Category 2: Sensors, instrumentation and control, operation, testing and maintenance, operator support, human-machine interface of nuclear power systems. 

Category 3: Integrated aspects of energy systems (i.e., multipurpose Utilization of nuclear energy, nuclear fuel cycle, plant decommissioning, comparative study of nuclear energy, etc.) 

Category 4: Other general nuclear engineering (i.e., reactor physics, thermal-hydraulics, reactor core and plant behavior, nuclear fuel behavior, etc.)