  The paper is about de-noising procedures aimed on events recognition in
signals from a distributed fiber-optic vibration sensor system based on the
phase-sensitive optical time-domain reflectometry. We report experimental
results on recognition of several classes of events in a seismic background. A
de-noising procedure uses the framework of the time-series analysis and
Kolmogorov-Zurbenko filtering. We demonstrate that this approach allows
revealing signatures of several classes of events.
