Experimental Study on Speech Articulation in Large Bus Cabin
The speech articulation in large bus cabin has the significant influence on the riding experience and driving safety.This study took the 48-seat bus for example,and combined objective acoustic parameters,e.g.,sound pressure level in cabin,reverberation time,and airborne sound insulation inside and outside cabin.The objective evaluation was integrated into subjective research.The quantitative evaluation models were constructed.The noise data from stationary and constant speed operation were continuously collected.It was revealed that the real acoustic environment inside the large bus cabin was influenced by the multiple complex excitation sources.The influence of listeners'position,pronouncers'gender,and operating conditions on speech articulation were analyzed to avoid the misunderstanding and misjudgment caused by speech articulation.The result indicates that the noise amplitude vary considerably in different regions.The speech intelligibility decreases with the distance increasing from the articulator's position,showing the non-normal distribution.The acoustic environment in the rear cabin of passenger area is the worst,and it is the threshold boundary value for speech articulation analysis.The acoustic environment in the front and center of passenger area is better and not significantly different.Due to the differences in duration,pitch and energy,the female speakers have better and more stable speech articulation than male speakers.In the case of speakers of same gender,there is a negative correlation between speech articulation and running speed.When the vehicle speed reaches 60 km/h,the overall data fluctuates greatly.The fluctuation of speech articulation data reaches peak with an average score dropping to 74.6.This study provides positive guidance for reducing noise interference in the large bus cabin and improving the acoustic environment inside cabin.It is suitable for optimizing the sound environment inside large bus.
NETL
NSTL
万方数据
