The Hartley transform, a real-valued alternative to the complex Fourier transform, is presented as an efficient tool for the analysis and simulation of earthquake accelerograms. This paper is introduced a novel method based on discrete Hartley transform (DHT) and radial basis function (RBF) neural network for generation of artificial earthquake accelerograms from specific target spectrums. Acce...

Beam broadening effects on the Doppler radar spectrum induced by alongand cross-radar-beam winds are theoretically investigated in this article. Analytical expression of beam broadening spectrum for a vertical beam subject to a constant vertical wind in the absence of horizontal wind is derived first. We find that the resultant beam broadening spectral shape is in an exponential form, rather th...

The statistics of a passive scalar in randomly forced and strongly stratified turbulence is investigated by numerical simulations including a horizontal passive scalar mean gradient. We observe that horizontal isotropy of the passive scalar spectrum is satisfied in the inertial range. The spectrum has the form Eθ(kh) = Cθεθε −1/3 K k −5/3 h , where εθ, εK are the dissipation of scalar variance ...

We present a new signal processing method that extracts the reference spectrum information from an acquired optical coherence tomography (OCT) image without a separate calibration step of reference spectrum measurement. The reference spectrum is used to remove the fixed-pattern noise that is a characteristic artifact of Fourier-domain OCT schemes. It was found that the conventional approach bas...

Recently, concerning failure of structures due to earthquakes, special investigations of near fault ground motions have been noticed. Hence, in this paper, characteristics of near field ground motions have been considered in horizontal and vertical directions. In this consideration, the record averages have been compared with Uniform Building Code and Eurocode8 spectra in two levels. In additio...

determination of boundary surface structures is commonly used for data interpretation. horizontal and vertical derivatives are useful tool for determining the edges boundary. using horizontal and vertical derivative in signal analysis method; that is effective method for interpretation of edges boundary, have been used commercially.in acquisition potential field data, using different methods of...

We present a simple two-step method by which one-dimensional spectra of horizontal velocity and buoyancy measured along a ship track can be decomposed into a wave component consisting of inertia–gravity waves and a vortex component consisting of a horizontal flow in geostrophic balance. The method requires certain assumptions for the data regarding stationarity, homogeneity, and horizontal isot...