Event recognition apparatus, event recognition method, and non-transitory computer-readable medium

An event recognition method using an event recognition apparatus, comprising:

• an acquisition step of acquiring an observation signal indicating sound or vibration that occurs at a point along an optical fiber and is detected by optical fiber sensing, and also acquiring a noise signal indicating optical noise being present at a point along the optical fiber;
• a derivation step of deriving, by using statistical information of a sound signal or a vibration signal acquired by a sound sensor or a vibration sensor, from the observation signal, a posterior probability that at least one event occurs at a point along the optical fiber, and also deriving, from the noise signal, a posterior probability that the at least one event occurs at a point along the optical fiber;
• and
• a comparison step of comparing a posterior probability derived from the observation signal with a posterior probability derived from the noise signal, deriving, from a result of the comparison, a posterior probability that the at least one event occurs at a point along the optical fiber, and outputting a result of the derivation.

A non-transitory computer-readable medium, storing a program causing a computer to execute:

• an acquisition procedure of acquiring an observation signal indicating sound or vibration that occurs at a point along an optical fiber and is detected by optical fiber sensing, and also acquiring a noise signal indicating optical noise being present at a point along the optical fiber;
• a derivation procedure of deriving, by using statistical information of a sound signal or a vibration signal acquired by a sound sensor or a vibration sensor, from the observation signal, a posterior probability that at least one event occurs at a point along the optical fiber, and also deriving, from the noise signal, a posterior probability that the at least one event occurs at a point along the optical fiber;
• and
• a comparison procedure of comparing a posterior probability derived from the observation signal with a posterior probability derived from the noise signal, deriving, from a result of the comparison, a posterior probability that the at least one event occurs at a point along the optical fiber, and outputting a result of the derivation.