1984 年 40 巻 2 号 p. 87-94
As is well-known, the wave form of random noise and vibration appearing in our actual enviroment shows usually the variety and the complexity in its fluctuation pattern. The statistical methods of analyzing and evaluating the above random wave form were studied by many researchers, from the viewpoint of signal analysis. In this paper, after first setting a generalized method of statistically evaluating the acuity of fluctuating random wave based on the information on each order of differntial type state variables, especially for the stational random wave of arbitarary distribution type, a new trial toward the statistical evaluation on the locations of level crossing, peak and trough has been concretely considered as the special cases, in close connection with the above differential type state variables. That is, in the proposed theory, the effect of usual linear correlations and non-linear correlations among two and/or many sampled points of random wave on the above probability distribution form of level crossing, peak and trough has been fully discussed under introduction of multivariate joint probability distribution. Finally, the practical effectiveness of the present theory has been experimentally confirmed too by applying it to the acrual road traffic noise wave obeserved ina suburb of a large city.