A PROBABILISTIC EVALUATION METHOD FOR VARIOUS TYPE SOUND INSULATION SYSTMES BASED ON KULLBACK'S INFORMATION CRITERION AND MIXED TYPE NON-STATIONARY SYSTEM MODE

摘要

In general, it is difficult to find some large scale model only from a bottom up way viewpoint for complicated sound insultion systems like non-parallel double wall or soundbridge type double wall. Furthermore, in the acual environment, the input fluctuates nonstationarily and the output is observed under contamination of the background noise. In this paper, for the above complicated systems with non-stationary random input, a new evaluation method is proposed by newly introducing a multiplicative-additive system model on an intensiy scale. Owing to non-Gaussian property of input, output signals and background noise, the usual identification method such as least-squares error method is not appropriate. So, a new identification method based on Kullback's information criterion is proposed to deal with the non-Gaussian property. Next, the method predicting the response output probability distribution for arbitrary random input without contamination of the background noise is proposed. Here, according to original non-negative property of intensity quantity, a statistical type Lagueme series expansion is first employed as the output probability distribution form. Its expansion coefficients can be predicted by employing the above identified model. Finally, the proposed method is experimental y confirmed too by applying it to the actual sound insulation systems.