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...

In this study, nonlinear vibration of a composite cable is investigated by considering nonlinear stress-strain relations. The composite cable is composed of an aluminum wire as reinforcement and a rubber coating as matrix. The nonlinear governing equations of motion are derived about to an initial curve and based on the fundamentals of continuum mechanics and the nonlinear Green-Lagrangian stra...

in this paper, optimum location of power system stabilizers in order to damp inter-area oscillations has been investigated by using modal series method. nonlinear effects grow in dynamical behaviors of heavily loaded stressed power systems significantly. hence linear based methods and techniques no longer present clear and exact response of the systems. in this article by defining new nonlinear...

In this paper a simple tool for seismic design of steel structures for a selected ductility level is presented. For this purpose, a consistent set of earthquakes is selected and sorted based on the maximum acceleration of ground surface. The selected records are applied as the base motion to a single-degree-of-freedom system with strain hardening and the maximum response acceleration is determi...

Nonlinear optics is a broad field of research and technology that encompasses subject matter in the fields of physics, chemistry, biology, and engineering. The diversity of nonlinear optics stems, in part, from the need for all-optical and electrooptical devices for applications in telecommunications, optical storage, and all-optical computing. In addition, many nonlinear optical effects have p...

We modify the public PM code developed by Anatoly Klypin and Jon Holtzman to simulate cosmology with arbitrary initial power spectrum and equation of state of dark energy. With this tool in hand, we perform the following studies on the matter power spectrum. With an artificial sharp peak at k ∼ 0.2hMpc in the initial power spectrum, we find that the position of the peak is not shifted by nonlin...

I present a general discussion of the evolution and model-dependence of both the linear and nonlinear power spectrum of density fluctuations. The features of the linear power spectrum in cosmological models with cold dark matter (CDM) and cold+hot dark matter (C+HDM) are reviewed, and useful analytical approximations are summarized. Cosmological numerical simulation results are then used to ill...