Amol, Iran
Amol, Iran

the Shomal University, Amol Most of the middle East Wikipedia.

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Bayat M.,Shomal University | Barari A.,University of Aalborg | Shahidi M.,Shomal University
Mechanika | Year: 2011

The current research deals with application of a new analytical technique called Energy Balance Method (EBM) for a nonlinear problem. Energy Balance Method is used to obtain the analytical solution for nonlinear vibra-tion behavior of Euler-Bernoulli beams subjected to axial loads. Analytical expressions for geometrically nonlinear vibration of beams are provided. The effect of vibration amplitude on the nonlinear frequency is discussed. Com-parison between Energy Balance Method results and those available in literature demonstrates the accuracy of this method. In Energy Balance Method contrary to the con-ventional methods, only one iteration leads to high accu-racy of the solutions which are valid for a wide range of vibration amplitudes.


Nobahari M.,Islamic Azad University at Neyshabur | Seyedpoor S.M.,Shomal University
Structural Engineering and Mechanics | Year: 2013

An efficient method is proposed here to identify multiple damage cases in structural systems using the concepts of flexibility matrix and strain energy of a structure. The flexibility matrix of the structure is accurately estimated from the first few mode shapes and natural frequencies. Then, the change of strain energy of a structural element, due to damage, evaluated by the columnar coefficients of the flexibility matrix is used to construct a damage indicator. This new indicator is named here as flexibility strain energy based index (FSEBI). In order to assess the performance of the proposed method for structural damage detection, two benchmark structures having a number of damage scenarios are considered. Numerical results demonstrate that the method can accurately locate the structural damage induced. It is also revealed that the magnitudes of the FSEBI depend on the damage severity.


Nobahari M.,Islamic Azad University at Neyshabur | Seyedpoor S.M.,Shomal University
Mathematical and Computer Modelling | Year: 2011

An efficient optimization procedure is proposed to detect multiple damage in structural systems. Natural frequency changes of a structure are considered as a criterion for damage presence. In order to evaluate the required natural frequencies, a finite element analysis (FEA) is utilized. A modified genetic algorithm (MGA) with two new operators (health and simulator operators) is presented to accurately detect the locations and extent of the eventual damage. An efficient correlation-based index (ECBI) as the objective function for the optimization algorithm is also introduced. The numerical results of two benchmark examples considering the measurement noise demonstrate the computational advantages of the proposed method to precisely determine the sites and the extent of multiple structural damage. © 2011 Elsevier Ltd.


Saadati R.,Amirkabir University of Technology | Saadati R.,Shomal University | Park C.,Hanyang University
Computers and Mathematics with Applications | Year: 2010

Lee et al. considered the following quadratic functional equation f(lx+y)+f(lx-y)=2l2f(x)+2f(y) and proved the HyersUlamRassias stability of the above functional equation in classical Banach spaces. In this paper, we prove the HyersUlamRassias stability of the above quadratic functional equation in non-Archimedean L-fuzzy normed spaces. © 2010 Elsevier Ltd. All rights reserved.


Eisazadeh A.,University of Technology Malaysia | Eisazadeh H.,Shomal University | Kassim K.A.,University of Technology Malaysia
Synthetic Metals | Year: 2013

In this research, natural sand and clay coated with polyaniline and iron oxide were used to remove Pb(II) from contaminated water. Fixed bed column and batch studies were performed to evaluate the influence of various experimental parameters such as pH, adsorbent dosage, and contact time. Based on the results, optimum conditions for Pb(II) removal were found to be pH 11, adsorbents dosage of 10 g/L, and contact time of 45 min. In addition, the morphology and chemical structure of the adsorbents were studied via scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The column tests were conducted with a flow rate of 4 mL/min with different bed depths of 10 and 25 cm. It was found that when iron oxide/clay, iron oxide/sand, polyaniline/clay and polyaniline/sand were used as adsorbent in a fixed-bed column method, the removal percentages of Pb(II) were 97.50, 99.24, 72.99, 68.80% and for the completely mixed batch reactor (CMBR) method were 99.84, 99.89, 93.91 and 90.77%, respectively. These results indicated that iron oxide coated sand and clay are an attractive source of adsorbents that can be used for removal of Pb(II) in water treatment processes. © 2013 Elsevier B.V. All rights reserved.


Bayat M.,Shomal University | Abdollahzadeh G.,Babol Noshirvani University of Technology
Latin American Journal of Solids and Structures | Year: 2011

The behavior of braced steel frame structures is of special importance due to its extensive use. Also the application of active and semi-active control systems, regarding to their benefits in obtaining better seismic performance has increased significantly. The majority of the works on steel structures and steel connections has been done under far field records, and the behavior of steel frame structures equipped with yielding dampers under these circumstances has not yet been fully analyzed. The main purpose of this paper is to determine the behavior of structures equipped with yielding dampers, located in near field based on energy concepts. In order to optimize their seismic behavior, the codes and solutions are also presented. The selected system is a braced steel frame system which is equipped with yielding dampers and the analysis is performed using the Perform 3D V.4 software and the conclusions are drawn upon energy criterion. The effect of PGA variation and height of the frames are also considered in the study. Finally, using the above mentioned results, a proper solution is presented for typical systems in order to increase the energy damping ability and reduce the destructive effects in structures on an earthquake event, so that a great amount of induced energy is damped and destruction of the structure is prevented as much as possible.


Bayat M.,Shomal University | Abdollahzadeh G.,Babol Noshirvani University of Technology
Latin American Journal of Solids and Structures | Year: 2011

The usefulness of supplementary energy dissipation devices is now quite well-known in earthquake structural engineering for reducing the earthquake-induced response of structural systems. The seismic behavior of structures with supplemental ADAS devices is concerned in this study. In this paper, the ratio of the hysteretic energy to input energy is compared in different structural systems. The main purpose of this paper is to evaluate the behavior of structures equipped with yielding dampers (ADAS), located in far fields based on energy concepts. In order to optimize their seismic behavior, the codes and solutions are also presented. Three cases including five, ten and fifteen-story three-bay Concentric Braced Frames (CBF) with and without ADAS were selected. The PERFORM 3D.V4 software along with three earthquake records (Northridge, Imperial Valley and Tabas) is used for nonlinear time history analysis and the conclusions are drawn upon energy criterion. The effect of PGA variation and height of the frames are also considered in the study. Finally, to increase the energy damping ability and reduce the destructive effects in structures on an earthquake event, so that a great amount of induced energy is damped and destruction of the structure is prevented as much as possible by using ADAS dampers.


Seyedpoor S.M.,Shomal University
Advances in Structural Engineering | Year: 2011

An efficient method is proposed to detect the multiple damages of structural systems. Natural frequency changes of a structure are considered as a criterion for damage presence. Finite element method is also employed to evaluate the required natural frequencies. A multi-stage optimization approach based on the swarm intelligence algorithm is presented to accurately identify the locations and extent of eventual damages. Test example results demonstrate the computational advantages of the proposed method to precisely determine the sites and extent of multiple structural damages.


Hasani T.,Babol Noshirvani University of Technology | Eisazadeh H.,Shomal University
Synthetic Metals | Year: 2013

Polypyrrole was successfully synthesized by using ferric chloride as an oxidant in the presence of sodium dodecylhydrogensulfonate, poly(vinyl pyrrolidone) and poly(vinyl alcohol) as surfactants in aqueous media. The effect of polypyrrole and its nanocomposites for the removal of Cd (II) was investigated. The products were characterized in terms of, morphology and chemical structure. The FTIR spectra show that the intensity of peaks was related to the type of surfactant. The crystalline nature of nanocomposites was determined from XRD analysis. The extra peaks in the XRD pattern of nanocomposites indicate the presence of Al2O3 nanoparticles in the polypyrrole matrix. The aim of this research was to investigate the sorption characteristic of polypyrrole nanocomposites for the removal of Cd (II) from aqueous solution. The removal percentage of Cd (II) was carried out by using batch method. The optimum conditions of sorption were found to be: contact time of 45 min and pH 5. The Langmuir and Freundlich model are subjected to sorption data to estimate the sorption capacity and intensity. The data was better fitted by using Langmuir model. © 2013 Published by Elsevier B.V.


Seyedpoor S.M.,Shomal University
International Journal of Non-Linear Mechanics | Year: 2012

A two-stage method is proposed here to properly identify the site and extent of multiple damage cases in structural systems. In the first stage, a modal strain energy based index (MSEBI) is presented to precisely locate the eventual damage of a structure. The modal strain energy is calculated using the modal analysis information extracted from a finite element modeling. In the second stage, the extent of actual damage is determined via a particle swarm optimization (PSO) using the first stage results. Two illustrative test examples are considered to assess the performance of the proposed method. Numerical results indicate that the combination of MSEBI and PSO can provide a reliable tool to accurately identify the multiple structural damage. © 2011 Elsevier Ltd. All rights reserved.

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