This abnormality diagnosis system for diagnosing abnormalities in a plant is provided with: an abnormality diagnosis control unit which, with respect to an instrument parameter measured in a plant determined to have an indication of abnormality, predicts the development of the instrument parameter by extrapolation, and which generates an abnormality manifestation pattern that is a pattern of behavior of the instrument parameter after prediction; and a data storage unit which stores a plurality of abnormality model patterns PA, PB that are patterns of behavior of the instrument parameters corresponding to causes CA1, CA2, CB1, CB2 of plant abnormality. The abnormality diagnosis control unit makes a matching determination between the abnormality manifestation pattern that has been generated and the plurality of abnormality model patterns PA, PB stored in the data storage unit, and identifies, as the cause of the abnormality in the abnormality manifestation pattern.

A process signal control and monitoring system, includes: a signal processing device which is installed on an outside of a nuclear reactor containment vessel, an internal electrical power source, an analog-digital conversion part, an internal communication part which transmits the digital signal to the signal processing device, an internal repeater, and an external repeater which transmits the received signal to a communication satellite. When electric power supply from the signal processing device is disconnected, the internal electrical power source supplies electric power which is charged in the rechargeable battery, to the analog-digital conversion part and the internal communication part; and the internal communication part judges whether communication with the signal processing device is continued or disconnected; and when the communication is judged to be continued, the internal communication part continues transmitting the digital signal to the signal processing device.

A process signal control and monitoring system, includes: a signal processing device which is installed on an outside of a nuclear reactor containment vessel, an internal electrical power source, an analog-digital conversion part, an internal communication part which transmits the digital signal to the signal processing device, an internal repeater, and an external repeater which transmits the received signal to a communication satellite. When electric power supply from the signal processing device is disconnected, the internal electrical power source supplies electric power which is charged in the rechargeable battery, to the analog-digital conversion part and the internal communication part; and the internal communication part judges whether communication with the signal processing device is continued or disconnected; and when the communication is judged to be continued, the internal communication part continues transmitting the digital signal to the signal processing device.

A system for sensing a UF.sub.6 gas leak in a nuclear fuel manufacturing process is proposed. The system is configured to sense whether or not there is a UF.sub.6 gas leak by optically detecting UO.sub.2F.sub.2 in a solid state generated due to a reaction with outside air, and thus to allow prevention of damage to a detection apparatus by means of sensing in a non-contact manner whether or not there is a UF.sub.6 gas leak, and to realize extension of mechanical life and reduction of the maintenance and repair cost for the detection apparatus.

A nuclear reactor protection system includes a plurality of functionally independent modules, each of the modules configured to receive a plurality of inputs from a nuclear reactor safety system, and logically determine a safety action based at least in part on the plurality of inputs; and one or more nuclear reactor safety actuators communicably coupled to the plurality of functionally independent modules to receive the safety action determination based at least in part on the plurality of inputs.

A device and method for inspecting and measuring weld defects in a cylindrical wall of a cylindrical conduit. The device can include an inspection head forming a probe having a proximal end and a distal end along its longitudinal axis, and of which a first side called “inner side” is provided with at least one ultrasound wave transducer. The inspection head can include a second side, called “outer side” opposite the first side that has a curved surface in the form of a cylinder fraction, and wherein the curved surface of the second side has outward facing convexity. The wave transducer can be formed of a series of juxtaposed elements, each element being both a transmitter and receiver, wherein a surface of the series is curved and in the form of a cylinder fraction, and wherein the surface of the series has outward facing concavity.

A process of evaluating and reducing outages in a power plant comprises acquiring analytical data for a power plant and its components, acquiring failure modes regarding power plants, identifying and categorizing the acquired failure modes in association with the components of the power plant at various levels, evaluating and ranking the significance of each of the identified failure modes based on the analytical data, evaluating and ranking the analytical coverages of the identified failure modes based on the analytical data, and ranking and evaluating the components based on the significance and the analytical coverages of their associated failure modes. Based upon the determined significance and analytical coverages of identified failure modes, a power plant owner is able to evaluate the performance of a power plant at various levels, identify analytical gaps in reducing outages of the power plant, and enhance the performance of the power plant.

An automated system for on-line monitoring and coil diagnostics of rod position indicator (RPI) coils coil diagnostic, or RPI coil diagnostic system. The RPI coil diagnostic system performs coil diagnostics for a RPI system in a nuclear power plant. The RPI coil diagnostic system is in electrical communication with and monitors the outputs of the detector coils. The RPI coil diagnostic system measures characteristics of the detector coils that are indicative of the health of the detector coils and/or the connections between the detector coils and the RPI electronics.

An automated system for on-line monitoring and coil diagnostics of rod position indicator (RPI) coils coil diagnostic, or RPI coil diagnostic system. The RPI coil diagnostic system performs coil diagnostics for a RPI system in a nuclear power plant. The RPI coil diagnostic system is in electrical communication with and monitors the outputs of the detector coils. The RPI coil diagnostic system measures characteristics of the detector coils that are indicative of the health of the detector coils and/or the connections between the detector coils and the RPI electronics.

A nuclear reactor protection system includes a plurality of functionally independent modules, each of the modules configured to receive a plurality of inputs from a nuclear reactor safety system, and logically determine a safety action based at least in part on the plurality of inputs; and one or more nuclear reactor safety actuators communicably coupled to the plurality of functionally independent modules to receive the safety action determination based at least in part on the plurality of inputs.