In methods using one temperature detection means and integrating the degree of temperature variation in a diaper, such as those used by existing devices, the ability to accurately estimate the amount of urine declines sharply the second time and thereafter. In particular, the flow path of the urine varies greatly depending on the posture of the subject during urination, further decreasing estimation accuracy. For these reasons, when diaper changes are performed on the basis of alerts from the existing devices regarding the amount of urine in a diaper, when the diaper is opened, the diaper may not yet need to be changed, or it may already have leaked urine. Improvements are necessary to solve these problems. [Solution] The amount of urine is calculated by providing: a plurality of temperature sensors disposed on the outside of a diaper a peak value calculation means for calculating the peak temperature value detected by each of the temperature sensors a reference temperature calculation means for detecting the temperatures at the points at which the temperatures detected by each of the sensors begin to rise due to urination or defecation, and establishing those temperatures as reference temperatures, and a weighted addition means for calculating urination and/or defecation amounts by performing a weighted addition of all of the peak values, on the basis of the results of subtracting the reference temperature for each temperature sensor, as calculated by the reference temperature calculation means, from the peak values generated by each temperature sensor, each time the temperature sensors respond to urination or defecation.Dans les procédés utilisant un moyen pour détecter la température et intégrant le degré de variation de la température dans une couche, tels que ceux utilisés par les dispositifs existants, laptitude à estimer avec précision la quantité durine décline considérablement la deuxième fois et les suivantes. En particulier, le trajet découlement de lurin
