فهرست مطالب hossein ghaffarzadeh

In the present paper, the improved sliding mode control algorithm are presented. This strategy is based on the combination of sliding mode control and Bang-Bang control theory. The Bang-Bang theory can switch abruptly between the on and off situation, this property can improve the performance of sliding mode control strategy. Also, three thresholds used to decrease the time of using the control system and optimizing the responses of structure.

The present paper investigates the operation of the sliding mode on three-dimensional benchmark building with smart base isolation to reducing the dynamic responses of seismically excitation. According to the being three-dimensional, interweaving responses of the structure with each other, cohesiveness of behavior of superstructure and base level and computing the nonlinear force of base isolation systems, this building is very complex. Under these circumstances, we used extended sliding mode theory to applying the benchmark building. Also, the actuators are located only at the base level and in the two main directions. The results indicate that the proposed control system improved the building responses.

A variety of numerical methods were developed for the wave propagation analysis in the field of structural health monitoring. In this framework, meshless methods are suitable procedure for the analysis of problems such as damage initiation and its propagation or the fracture of materials. In this study, Hermit-type radial point interpolation method (HRPIM) is investigated for the numerical modeling of flexural wave propagation and damage quantification in Euler-Bernoulli beams using MATLAB. This method employs radial basis function (RBF) and its derivatives for interpolation which leads to Hermitian formulation. The evaluation of performance and capability of HRPIM is based on the comparison between the captured HRPIM ang benchmark signals using the root mean square error (RMSE) and reflection ratio from damage. The algorithm of damage quantification is the analytical solution which relates the reflection ratio to the damage extent. In this study, Gausian-type RBF is utilized and the number of field nodes, the size of support domain, shape parameters of RBF, the number of polynomials in the interpolation formula, the arrangement of background cells and the number of Gaussian points in damage length are the effective parameters on results. Based on the evaluation, the acceptable values and range of theses parameters are presented for correct modeling.