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Based on social identity and attribution theory and the results of hitherto empirical researchs, the relationship between corporate social responsibility and behavioral outcomes is explainable But the relationship between CSR with the expected don’t seem so clear. In other words, the mechanism of employee behavior variant in regard to corporate social responsibility remains unclear. The purpose of this causal-relationship research was to identify the variables affecting the relationship between CSR and agriculture experts' job commitment. Based on Cochran formula, 135 of them were selected through quota sampling method. The main method was prediction orientation segmentation algorithms to identify the unknown variables affecting the relationship between two variables. The results showed that the effect of corporate social responsibility in development of employee commitment is relatively complex, evolutionary and gradually. This means that to achieve the desired results of corporate social responsibility, the continuation of the goals of its dimensions can play an important role in employees attribution. It also became clear with over time of employee resident at organization, their interpretation of CSR and as a result its effect on their commitment, would be differ. Thus, indirectly, it could be said that social identity theory can play intermediate variable role in study of CSR effects.

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One of the challenging tasks for civil engineers is to mitigate the response of structures that are subjected to dynamic loads in order to prevent possible damages that may cause human and enormous economic losses.To minimize vibration, reduction of the external disturbance to a system is always preferred, but in many cases, this may not be possible. Modification of the system to avoid resonance may entail significant redesign. Furthermore, it would be difficult to be applied to existing structures. Thus, vibration control devices, which can be simply attached to the existing system to reduce the vibration without drastically altering the original system, have been developed. Passive tuned mass damper (TMD), whose concept was presented more than a century ago, is undoubtedly a simple, inexpensive and reliable means to suppress unfavorable vibrations of structures but the very narrow band of suppression frequency, the ineffective reduction of non-stationary vibration, and the sensitivity problem due to detuning are the inherent limitations of the passive TMDs. TMDs are usually tuned to the first natural frequency of the structures. Since TMD parameters are constant during the life cycle of the structure, it is important to adjust them properly to achieve a favorable performance. Optimal values of TMD parameters for structures with non-linear behavior require non-linear dynamic analyses. There are many analytical and empirical relations to identify these parameters obtained by structure simplification and loading. In this paper, genetic algorithm (GA) is employed to find optimum TMD parameters for vibration control of the College Bridge in Tehran. With the length of 372 m, this steel bridge has 14 spans. The bridge is modeled in OpenSees environment. Verification of the finite element modelling is performed by comparing the results of the dynamic analyses under four earthquake records by those of another model created in SAP2000 software. In order to mitigate its vibrations, 11 TMDs are considered to be installed on the bridge. The aim of GA is to minimize the displacement of the tallest pier of the bridge in order to decrease the maximum displacement of the structure subject to earthquake excitations. Based on the analyses conducted for near-field and far-field earthquakes, it was concluded that employing GA considerably reduces convergence rate to achieve optimum TMD parameters. To evaluate the performance of a control system during severe earthquakes, incremental dynamic analyses (IDA) for maximum peak ground accelaration (PGA) of 0.1g to 1.0g was conducted. The longitudinal root mean square and maximum displacement of the tallest pier in uncontrolled and controlled cases are obtained and compared. The results of IDA analyses show that for low PGA values, TMDs by themselves absorb and dissipate a large portion of the input energy because in this case the piers remain elastic. However, for higher values of PGA, piers also dissipate some portion of input energy by entering nonlinear region. The percentage of response reduction for different earthquakes are not the same because each earthquake has its own frequency content. According to the numerical analyses for the mass ratio as 4%, the longitudinal displacement and reduced RMS displacement of the largest pier of bridge by tuned mass damper for El-Centro, Kern-County, Kobe and Northridge earthquakes are 24.9 and 34.3, 43.5 and 38.7, 30.6 and 40.4, 13.6 and 28.1 respectively.

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There is a debate among earthquake engineers that the structural and non-structural damages initially occur due to lateral loads caused by earthquake excitation. American provisions, including FEMA356 estimates structural performance by means of maximum deformation demand. However, in addition to the maximum deformation, residual displacement plays an important role in structural performance. Amplitude of residual displacement is an important parameter in technically and economically determining rehabilitation of damaged structures for resisting aftershocks. In this study, residual displacements of a five-story steel frame is designed with vertical link beam as well as the effect of vertical link beam length have been investigated. For vertical link beam, the IPE sections with typical steel is considered, instead of using boxes and H-shaped cross-section.The IPE section has some advantages than box section such as lower cost, easier installation and replacement. The Vertical link beams with IPE cross-section has been studied in 5 separate models with length of 20, 25, 30, 35 and 40 centimeters. In this paper, experimental results of a frame model with vertical link beam tested in structural laboratory of Building and Housing Research Center (BHRC) has been used for verification of numerical model. As one of the fastest nonlinear softwares, OpenSees (Open System for earthquake engineering simulation) has been used for structural modeling. The steel material that has been used in this model is uniaxial material steel 02. In the following, seven near field and seven far field earthquake acceleration time histories that scaled by 2800 standard, are used analysis of five-story and five-bay structure with chevron bracing system. According to the seismic design of structures if ductile elements is used in a structure, then beams and columns should remain elastic during earthquake, while ductile elements dissipate input energy by nonlinear behavior of ductile members. By considering of the results, the vertical link beam with length of 20 and 25 centimeter for far field earthquakes and 20 centimeter for near field earthquakes have the best performance compare to the other cases. The Bam earthquake is selected to investigate of hysteresis diagram of the vertical link beam energy dissipation. The results for near field earthquake like the Bam earthquake show that link beam with length of 40 centimeter with moment behavior, has low energy dissipation capability. Furthermore, the vertical link beam with 40 centimeter length causes more residual displacement and yielding. By considering the station with equal 104.28 km distance from center of earthquake can use the Bam record as a far field earthquake. In this case link beams with more than 25 centimeter length have more fluxing. However, the link beams with length of 20 and 25 centimeter have better seismic performance. Considering the RMS (Root Mean Square) parameter as a controller criterion the vertical link beam with length of 20 centimeter is more suitable for near and far field earthquakes. Considering the seismic performance parameters of vertical link beam like appropriate stiffness, high stability, energy dissipation capability, appropriate control of maximum response of structure and less residual displacement, the vertical link beam with length of 20 centimeter has the best seismic performance for near and far field earthquakes compare to the other cases.