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Bolt joints play an important role in the industries, so the estimation of fatigue life of bolts is an essential task. The aim of present study is estimation of fatigue life of connection bolts of two flanges in reinforced cylindrical shell with cutout. Two groups of data are needed for mentioned bolt: fatigue properties of bolt and value of stress of bolt due to applying load to structure. So, two paths have been gone. First, the fatigue properties of bolt have been measured in laboratory according to ISO 3800 standard. For this purpose a specific fixture was designed and manufactured which provided testing different bolts. By doing fatigue experiments, the fatigue properties of mentioned bolt such as fatigue limit and Basquin’s equation constants (fatigue strength coefficient and fatigue strength exponent) have been measured. Fracture mechanism and fracture surface have been investigated, too. Afterward, in the next step the value of stress in bolt that is subjected to mix loading has been calculated by using of FE modeling. Because of problem complexities, cost of three dimensional analysis of this problem increases, so analysis of the problem has been performed by shell-to-solid sub-modeling technique. At the end, by calculating the nominal stress of bolt from FE modeling and using fatigue properties witch obtained from experiments, life of the mentioned bolt has been estimated.

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The exchange rate overshooting, which results from the monetary disruptions, has negative impact on production and investment in the main economic activities and de-stabilizes the whole economy because of their input-output linkages. Therefore, identifying the causes of economic instability can help to adopt appropriate policies and to create economic stability in the country. The main question is to what extent the exchange rate can cause instability in the economy. To answer this question, first, the exchange rate overshooting was calculated using the Hodrick- Prescott filtering method during 1989-2012. Then, it was introduced into the model by specifying the generalized Solow production function, and finally, the production function was estimated for the main activities of the economy using the panel data technique. The results show that the impact of the exchange rate overshooting on the major economic activities is negative.