Abstract: A method of monitoring a plant by using a Mahalanobis distance calculated from data of a plurality of variables each of which indicates a state of the plant includes: a dividing step of dividing a range of a single variable which indicates a state of the plant into a plurality of first range bands on the basis of a frequency distribution of the single variable; and a unit space creating step of creating a plurality of unit spaces which serve as a basis of calculation of the Mahalanobis distance on the basis of the respective data of the plurality of variables respectively corresponding to a plurality of second range bands of the single variable determined on the basis of the plurality of first range bands.

Abstract: A plant monitoring device (20) is provided with: a detection value acquisition unit (211) that acquires a bundle of detection values; a first Mahalanobis distance calculation unit (212) that calculates a first Mahalanobis distance by using as a reference a unit space generated on the basis of a bundle of past detection values; a first SN ratio calculation unit (214) that calculates a first SN ratio for each of a plurality of evaluation items; a second Mahalanobis distance calculation unit (215) that calculates a second Mahalanobis distance by increasing or decreasing each of the detection values; a second SN ratio acquisition unit (216) that converts the first SN ratio for each of the evaluation items and acquires a second SN ratio on the basis of the first and second Mahalanobis distances; and an addition unit (217) that calculates an added value of a plurality of the second SN ratios acquired within a prescribed period for each of the evaluation items.

Abstract: A plant monitoring method using a Mahalanobis distance calculated from data of a plurality of variables indicating the state of the plant. The plant monitoring method includes: acquiring data in a first period in the past up to the current point of time as first data; predicting data in a second period from the current point of time as second data; and creating, on the basis of the first data and the second data, a unit space that serves as a base for calculating the Mahalanobis distance. In the prediction step, the second data is predicted on the basis of: data in a third period obtained, as third data, by shifting the first period to the past by a prescribed period; data in a fourth period obtained, as fourth data, by shifting the second period to the past by the prescribed period, and the first data.

Abstract: A computer-readable storage medium stores a data processing program for causing a computer to execute a process. The process includes: identifying a first combination of first data and second data based on a predetermined condition from a storage in which the first data and first ciphered data obtained by ciphering the first data are correspondently stored, and the second data and second ciphered data obtained by ciphering the second data are correspondently stored; extracting a second combination of the first ciphered data and the second ciphered data stored respectively and correspondently to the first data and the second data identified by the identifying; and transmitting the second combination of the first ciphered data and the second ciphered data extracted by the extracting to an external device.

Abstract: An anonymizing apparatus includes a processor configured to receive an instruction from a first apparatus, anonymize an anonymized part of a first data based on a type of an application program that causes the first apparatus to send the instruction, and transmit the anonymized first data to the first apparatus.

Abstract: A computer-readable storage medium stores a data processing program for causing a computer to execute a process. The process includes: identifying a first combination of first data and second data based on a predetermined condition from a storage in which the first data and first ciphered data obtained by ciphering the first data are correspondently stored, and the second data and second ciphered data obtained by ciphering the second data are correspondently stored; extracting a second combination of the first ciphered data and the second ciphered data stored respectively and correspondently to the first data and the second data identified by the identifying; and transmitting the second combination of the first ciphered data and the second ciphered data extracted by the extracting to an external device.

Abstract: An anonymizing apparatus includes a processor configured to receive an instruction from a first apparatus, anonymize an anonymized part of a first data based on a type of an application program that causes the first apparatus to send the instruction, and transmit the anonymized first data to the first apparatus.