Abstract: A method for protecting a programmable logic circuit includes storing data file(s) used for the configuration of the programmable resources of the circuit in a non-volatile memory after having been encrypted. A decryption module internal to the circuit is responsible for decrypting the file(s) by using a secret key stored in the circuit, the decryption module being protected against attacks aiming to obtain the key during the decryption operation by implementing at least one countermeasure technique.

Abstract: It consists of determining by an iterative calculation the neutron flux .phi.(j,g) at each point j of the core in the form of a sum of two components, the first component being associated with a predetermined state of the core defined by predetermined interaction probabilities of the neutrons in the core and the second component being linked with the real state of the core, with said predetermined state and with said first component. The power given off P(j) and the number of emitted neutrons S(j) at each point of the core are then deduced from the neutron flux. The power given off P(j) and the neutron flux .phi.(j,g) are used for controlling the core regulating means, such as the control rods or the boron concentration.