| "Numerous machines used to execute public works projects produce noise, and in the past noisemeasurements were performed assuming project noise is produced by a single sound source.But to perform practical noise prediction, the quantity of noise from each machine must beobtained. The authors analyzed simulated noise in semi-anechoic room and outdoorconstruction machinery noise with a straight microphone array installed horizontally tocalculate the quantities of noise produced by individual sound sources. Simulated noise insemi-anechoic room had been analyzed with target accuracy. But, with the outdoor movingsound sources, the total of the analysis values was reduced to between 2.4 and 4dB.Approximately -1dB is caused by applying the delay and sum, approximately -1dB is causedby installing a band pass filter, and the remaining -0.4 to -2dB is caused mainly by motion ofthe sound sources. The noise levels of individual sound sources are corrected by the total valuemeasured by a noise meter. And although not the purpose of this research, it was confirmedthat it is possible to analyze the location of a sound source based on the noise, and that thesound can be reproduced by sound source." |
