A trial of evaluation based on multiplicative multivariate model for non-stationary road traffic noise

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Authors

  • M. OHTA Department of Electronic Engineering and Computer Science, Faculty of Engineering, Kinki University, Japan
  • Y. FUJITA Department of Management and Information Science, Onomichi Junior College, Japan

Abstract

Since the non-stationary fluctuation of actual acoustic environment like the road traffic noise within a long time interval is usually caused not by the change of merely additional external noise but by the essential change of internal factors themselves, it is reasonable to give as a mathematical model of this non-stationary fluctuation not an additive model but a multiplicative model. In this paper, mainly from a methodological viewpoint, first, the characteristic function method of Mellin transform type for the above multiplicative model is introduced and a new unified expression form of the probability density function within a long time interval is derived in an expansion form based on the probability density function within a short time interval of local stationary type as its first expansion term with distribution parameters reflecting hierarchically various types linear and nonlinear correlation information.

References

[1] A. IKETANI, Mathematical model and evaluation indexes for road traffic noise [in Japanese], Acoust. Soc. Jpn., 81, 9, 559-565 (1975).

[2] M. OHTA et al., A prediction theory of sound level probability distribution in urban district for assessment of establishment of new road and experiment by simulation [in Japanese], Acoust. Soc. Jpn., 81, 2, 72-80 (1975).

[3] S. ISHI, A study on the calculation method of predicting a road traffic noise [in Japanese], Acoust. Soc. Jpn., 31, 8, 507-517 (1975).