Papers by Keyword: Fourier Transform Method

Abstract: A theoretical model is developed to investigate sound transmission characteristics of an infinite lightweight plate line connected to equally spaced stiffeners and excited by an oblique plane wave. The reactive forces and moments at the line connections are obtained from the flexural and torsional motions of the stiffeners. The vibro-acoustic equation that describes the dynamic response of the structure is derived by employing the Fourier Transform method, which will be numerically solved by truncating the solution to converge. Numerical examples are presented to investigate the effects of the incidence angle, the stiffener spacing, the plate thickness, on the sound transmission characteristic of the system, and useful conclusions are drawn.

Abstract: We propose a new method called the multi-dependent Hurst exponent to investigate the correlation properties of the nonstationary time series. The method is validated with the artificial series including both short-range correlated data and long-range correlated data. The results indicate that the multi-dependent Hurst exponents fluctuate around the a-priori known correlation exponent H. Application to traffic time series is also presented, and comparison is made between the artificial time series and traffic time series.