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Abstract Introduction: The aim of this study is to investigate the relationship between organizational procrastination and cognitive arousal and burnout.  Method: This research is descriptive–correlation and the required data are obtained by using three questionnaire about organizational procrastination, dissonance arousal reduction and burnout scales on a sample of 100 individuals in Tehran governmental employees who are randomly chosen. Results: The results of correlation coefficient show that organizational procrastination is positively and significantly associated with cognitive arousal (p ≤ 0.01, r=0.402) and burnout (p ≤ 0.01, r=0.432). However, the correlation coefficient between burn-out and cognitive arousal (p ≥ 0.05, r= 0.191) is not significant. The results of the analysis prove a direct relationship between organizational procrastination and burn-out and cognitive arousal does not play a mediation role. Finally, the model is verified. Conclusion: The organizational procrastination level has influence on burnout level among Tehran governmental employees. Hence, some interventions to reduce organizational procrastination are recommended to decrease the burn-out.   Keywords: Organizational Procrastination, Cognitive Arousal, Burnout, Tehran Governmental Employees

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In this paper, the effect of different workpiece geometries on the properties of welded Al-7075-T6 parts in rotational friction welding process has been investigated by using experimental and finite element approaches. Welding process is continuous drive friction welding. In this research, the samples diameter were selected equal to 25 mm and the samples length were selected equal to 75 mm. The process variables such as friction time (t1), forging time (t2), friction pressure (P1) and forging pressure (P2) where assumed to be constant, whereas, rotational speeds were variable and selected equal to 2000 rpm and 2500 rpm. Three cylindrical parts with different cross sectional geometries were adopted as three samples. Finally, to verify the accuracy of numerical analysis, the experimental and thermo-mechanical simulation results were compared and found a good agreement between them. Since, an experimental test is a time consuming and a costly process activity, it was decided to get more results by using an alternative method such as finite element simulation technique. Results of this study showed that changing in front geometric of workpiece is an effective factor for tensile strength, length of workpiece and generated flash in welded area and by changing this factor, properties of welded area can be improved.

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Biologic tissues modeling play an important role in understanding the tissue behavior and development of synthetic materials for medical applications. It is also a vital action to develop the predictive models for a wide range of uses including medical and tissue engineering. Various strain energy functions have been introduced to model arteries to date. The newest introduced strain energy function is the Nolan strain energy function. Two-layer arterial modeling using this strain energy function has not been performed so far. In this paper, modeling the arteries was carried out in the form of double layers including media and adventitia and hyperelastic material assumption. At first, governing equations were driven based on continuum mechanics. Boundary conditions including inner pressure of artery, axial load and torque as well as static equilibrium were applied. Moreover, Cauchy stress components were gotten by using the continuum mechanics relations. Then, the equilibrium equations in cylindrical coordinate were obtained by using the Cauchy stress. Stress distribution through the artery wall was specified by solving the resulting nonlinear partial differential equations based on generalized differential quadrature method. In the beginning, the artery modeling was conducted in the form of monolayer including the media layer and the results were compared with experimental ones, comparison between stresses in the artery wall and experimental data showed that the volcanic energy function of Nolan is suitable for modeling. After that, the stress distribution was obtained by artery modeling in the form of double layers including the media and adventitia layers.

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Organizational cynicism as one of the main problems of current organizations, has many negative consequences for the organizations in personal and organizational level. Therefor studying solutions for diminishing this phenomenon, is vital. Considering importance of ethical concerns in organizations, this paper studies the impact of ethical leadership on decreasing organizational cynicism directly and through the ethical climate. Cultural Heritage and Tourism Organization of Zanjan form the research population. Data gathered by standard questionnaire has been analyzed using structural equation modeling. Results show that there is not significant (direct negative) effect between ethical leadership and organizational cynicism, but if ethical leadership set the stage for flourishing ethical climate, it can decrease organizational cynicism. In this regard, the positive direct impact of ethical leadership on ethical climate has been confirmed.

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Knowledge sharing is one of the essential processes for implementing knowledge management and it would be accruing when helping others or learning for new capabilities. Nowadays, using organizational knowledge and sharing knowledge among knowledge-oriented organizations, employees has been considered to be a competitive advantage and along maintaining them. In order to achieve better situations and status, organizations and institutions follow some models and solutions to identify and simulate knowledge sharing motivational policies. Therefore this study was defined and presented to examine knowledge sharing motivational factors in organization. So, we aimed to examine knowledge sharing motivational factors using system dynamics method. At the beginning, we identified knowledge sharing motivational and non-motivational factors based on literature review and interviewing experts. Then, dynamic model was drawn based on dynamic systems methodology. After validating and verifying the model, research questions were answered in conclusion chapter.

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Merger is one of the most important changes that organizations experience. This change can have many effects and different aspects. The purpose of this research, is examination of the effect of merger on organizational identification and organizational legitimacy. Our society is the Ministry of Cooperatives labour and social welfare. In this regard, changes of organizational identification and organizational legitimacy before and after the merger have been studied. In this research, organizational identification has been studied based on expanded model of organizational identification (Misidentification, Ambivalent Identification & Neutral Identification); this means that the effect of merger on these types of organizational identification has been studied. In addition the impact of organizational legitimacy on organizational identification and misidentification, ambivalent identification & neutral identification, after merger has been studied. Finally the solutions for improving organizational identification have been presented based on the results.  
The results of the research show that in the ministry, the organizational legitimacy and organizational identification decreased significantly after the merger compared to before the merger, but misidentification, and ambivalent identification have increased significantly, although the changes of neutral identification was not significant. Based on the results of the post-merger phase, it was revealed that organizational legitimacy has a direct impact on organizational identification and has an inverse impact on the 3 types of organizational identification based on expanded model of organizational identification.