The Uncertainty of Noise Composed of Separate Sound Events

Abstract

Transportation noise is a main source of noise pollution. It is assumed that it consists of recognizable noise events which come from moving aircrafts, trains and boats. The noise of an isolated sound event is assessed by the sound exposure level, LAE. Much legislation and many regulations and guidelines employ the A-weighted time-average sound level, LAeq,T , with the time interval T of one hour or longer. LAE measurements enable an approximation of LAeq,T . The key point is the uncertainty of this approximation. It has been shown that an increase in the number of LAE categories brings about a decrease in uncertainty. For illustrative purposes, LAE measurements of aircrafts taking off and landing were carried out.

A study of the performance of a generalized exceedance algorithm for detecting noise events caused by road traffic

“…However, road traffic can have much shorter vehicle headways, resulting in problematic event detection and counting, even at moderate traffic flow rates [25][26][27]. Apart from their role in potentially explaining human response to certain traffic noise conditions, there is also an interest in road traffic noise events as an intermediate step in the estimation of energy measures of the whole traffic flow noise signal, or in the estimation of uncertainty measures due to the variability of the acoustic sources in time (as in [28]). The latter applications are not considered further in this paper.…”

Missing values reconstruction in sound level monitoring station by means of intelligent computing

“…Based on the measurements that were conducted 24 hours a day, the equivalent sound levels were calculated for three time periods: day (6 a.m. to 6 p.m.), evening (6 p.m. to 10 p.m.), and night (10 p.m. to 6 a.m.) [3]. The noise pollution (nuisance) due to long-term exposure to noise is very often measured by the equivalent sound level (L Aeq,T ), expressed in (dB), defined as [4] [ ∫ ( ( ) ) ] ,…”