Dampers can reduce structural response under dynamic loads. Since dampers are costly, the design of structures equipped with dampers should make their application economically justifiable. Among the effective cost reduction factors is optimal damper placement. Hence, this study intended to find the optimal viscous damper placement using efficient optimization methods. Taking into account the no...

A proper composition of stiffness and ductility parameters is required to obtain a resistant and economic structure. Accordingly, Chevron Knee Braced Frame (CKBF) seems appropriate due to its proper seismic performance. The advantage of this system comes to having the capability of rapid and cheap replacement of chevron knee elements after an earthquake occurs. In this research, response modifi...

the sirri jacket offshore platform was designed and installed in persian gulf of iran in 1975 and has been in service since that time. the importance of offshore structure's stability and the failure of this kind of structure during an earthquake in different active zones revealed that earthquake loading has to be considered. in this paper, magnetorheological (mr) fluid dampers have been propos...

To design a good control system, it is essential to have accurate dynamic models of the system being controlled. Frequency response techniques can be used to develop such dynamic models. In this paper, a new approach for direct solution of the frequency response of 2D heat transfer problems with nonlinear source terms and dynamic boundary conditions is proposed. Three typical boundary condition...

Nonlinear dielectric spectroscopy (NLDS) was used to detect interaction of a pulsed magnetic field (PMF) with membrane protein dynamics in aggregating Dictyostelium discoideum amoebae. In the experiments reported here, a strong nonlinear dielectric response of Dictyostelium discoideum cells is shown, and a distinctive nonlinear dielectric response of cells previously exposed to PMF is shown. Th...

in this paper we have discussed the main features of a finite clement program which we have developed for nonlinear dynamic analysis of plates and shells with material and geometric nonlinear behaviour. for this purpose, initially, the finite element model which we have used is briefly described. afterwards, the nonlinear viscoplastic material model in one-dimensional and multi-dimensional medi...

Recently, we have proposed a new image device called gigavision camera whose most important characteristic is that pixels have binary response. The response function of a gigavision sensor is non-linear and similar to a logarithmic function, which makes the camera suitable for high dynamic range imaging. One important parameter in the gigavision camera is the threshold for generating binary pix...

a dynamic two dimensional problem of thermoelasticity with double porous structure has been considered to investigate the disturbance due to normal force and thermal source. laplace and fourier transform technique is applied to the governing equations to solve the problem. the transformed components of stress and temperature distribution are obtained .the resulting expressions are obtained in t...

Genetic programming can be used to evolve an algebraic expression as part of an equation representing measured input-output response data. Parts of the nonlinear differential equations describing a dynamic system are identified along with their numerical parameters using genetic programming. The results of several such optimisations are analysed to produce a nonlinear physical representation of...

Stochastic amorphous Pd43Ni10Cu27P20 foams were tested in quasistatic and dynamic loading. The strength/porosity relations show distinct slopes for the two loading conditions, suggesting a strain-rate-induced change in the foam yielding mechanism. The strength/porosity correlation of the dynamic test data along with microscopy assessments support that dynamic foam yielding is dominated by plast...