Abstract: According to an embodiment, a neutron measurement apparatus has: a neutron detector; a preamplifier that amplifies an output signal of the neutron detector and outputs a neutron detection signal; a pulse counting unit that measures the neutron intensity by using pulse counting method by which the neutron detection signal is used to count the number of individual pulses; a Campbell measurement unit that measures the neutron intensity by using Campbell method by which a time average of squares of AC component of the neutron detection signal is calculated; a correction constant calculation unit that calculates a correction constant for correcting an output of the Campbell measurement unit by using an output of the pulse counting unit and an output of the Campbell measurement unit; and a correction value calculation unit that outputs, based on the output of the Campbell measurement unit, a corrected value by using the correction constant.

Abstract: According to one embodiment, reactor oscillation power ranges monitor includes: a receiving unit which receives LPRM signals; an exclusion processing unit which searches the LPRM signals allocated to the cell for an LPRM signal corresponding to an exceptional condition; an averaging unit which averages the allocated LPRM signals; a time averaging unit which calculates a time average of the average flux value; a normalized value calculation unit which divides the average flux value by the time averaged flux value; an initialization unit which outputs an initialization signal identifying the cell allocated to an LPRM signal which is changed to correspond or not correspond to the exceptional condition; and a determination unit which derives at least one of amplitude and cycle of a power oscillation from the normalized value.

Abstract: According to an embodiment, a neutron measurement apparatus has a neutron detector; a pre-amplifier; a first AC amplifier which extracts and amplifies an AC component; a bandwidth limiter which obtains a signal of a range of a predetermined frequency domain based on the output of the first AC amplifier; a neutron signal interval calculation unit which derives a neutron signal interval, that is a period of time during which a significant signal is being generated, from the AC component of the neutron detection signal; and a mean square value calculation unit which calculates a mean square value of outputs of the bandwidth limiter for a range corresponding to the neutron signal interval.

Abstract: According to an embodiment, a neutron measurement apparatus has: a neutron detector; a preamplifier that amplifies an output signal of the neutron detector and outputs a neutron detection signal; a pulse counting unit that measures the neutron intensity by using pulse counting method by which the neutron detection signal is used to count the number of individual pulses; a Campbell measurement unit that measures the neutron intensity by using Campbell method by which a time average of squares of AC component of the neutron detection signal is calculated; a correction constant calculation unit that calculates a correction constant for correcting an output of the Campbell measurement unit by using an output of the pulse counting unit and an output of the Campbell measurement unit; and a correction value calculation unit that outputs, based on the output of the Campbell measurement unit, a corrected value by using the correction constant.

Abstract: A radiation monitoring system includes: a signal transmitting unit gives a discrimination ID of a sensor that detects radiation, to a data signal based on an output of the sensor, and transmits the data signal to a lower network; a calculation unit calculates various amounts on a basis of the data signal that is received via the lower network using the discrimination ID as a key, and transmits the various amounts to an upper network; and a display unit displays information on the various amounts that are received via the upper network using the discrimination ID as a key.

Abstract: An oscillation power range monitor has: an averaging section that assigns a plurality of LPRM readings input filtered to remove noise thereof from local power range monitors to calculate cell average value of the LPRM readings assigned to each cell; a time average processing section that calculates a cell time average value from the average value of each cell; a normalized cell value computing section that computes the normalized cell value for each cell from the cell time average value and the cell average value; a trip determining section that receives the normalized cell value, monitors oscillations of each cell output and outputs a scram trip when the normalized cell value exceeds a predetermined value; and an abnormality determining section that assigns a plurality of LPRM readings input and determines abnormality of each LPRM reading assigned to each cell based on the oscillations of the LPRM reading.

Abstract: An oscillation power range monitor has: an input signal processing section that calculates a normalized cell value from LPRM signals input from local power range monitors; a soundness checking basic signal generating section that generates a simulated cell value that is variable on a time series basis; and a trip determining section that receives the normalized cell value and the simulated cell value respectively from the input signal processing section and the soundness checking basic signal generating section as input, compares the normalized cell value and the simulated cell value with a determination threshold value and outputs a scram trip signal when either of them exceeds the determination threshold value.

Abstract: According to one embodiment, reactor oscillation power ranges monitor includes: a receiving unit which receives LPRM signals; an exclusion processing unit which searches the LPRM signals allocated to the cell for an LPRM signal corresponding to an exceptional condition; an averaging unit which averages the allocated LPRM signals; a time averaging unit which calculates a time average of the average flux value; a normalized value calculation unit which divides the average flux value by the time averaged flux value; an initialization unit which outputs an initialization signal identifying the cell allocated to an LPRM signal which is changed to correspond or not correspond to the exceptional condition; and a determination unit which derives at least one of amplitude and cycle of a power oscillation from the normalized value.