Implementation and comparison of least-square method and thin-plate spline method for PWR online power-distribution monitoring based on NECP-ONION system

•The least-square method (LSM) is implemented in the NECP-ONION system.•The thin-plate spline method (TPSM) is implemented in the NECP-ONION system.•The key parameters have important impact on the online monitoring methods.•The key parameters are determined based on the uncertainty requirement.•The LSM and TPSM are compared based on the BEAVRS benchmark.