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Following Northridge earthquake, wide spread brittle cracking had been observed in steel moment connection, and this, was in contrast with the philosophy of designing steel moment frames which accounts for dissipating energy by forming plastic hinges at beams. This situation led to the development of improved connections to make them less prone to brittle fracture. However, studies have shown that these new connections, typically known as post-Northridge connections, can still have the tendency to fracture but in a ductile manner when subjected to ultra low cycle fatigue loading. Ultra low cycle fatigue loading consists of limited cycles of loading with large amplitude which induce strains that are several times greater than yielding. Searching the literature, varied methods have been proposed to predict cracking in ductile steel for both monotonic and cyclic loading.
In this research, a micro mechanical model called cyclic void growth model has been applied to predict the instance and location of cracking in the steel structure. For the purpose of predicting the low cycle fatigue failure, finger shaped steel moment type connections with top and bottom cover plates which their experimental data were available, used as a benchmark study. A micro mechanical model is integrated into the ABAQUS finite element program in order to simulate crack initiations in the cover plate welded beam to column connection. For this purpose, a Fortran code is linked with the ABAQUS software for simulating the crack and specifically to predict when and where the crack initiates. By understanding the crack initiation and the location of this crack, a trend line for low cycle fatigue under various constant drift angels are put together. The trend line provides a number of cycles for the crack to initiate by applying the specific drift angle. Therefore, a finite element model of a cover plate welded moment connection was developed and was used in order to simulate cracking in the connection model. Thus, each crack location and the number of cycles to initiate the crack were detected. Utilizing cyclic void micro mechanical model of growth analysis, which is a technique to predict fracture in a ductile material, different cover plate connections were modeled in the steel moment frame, and then their critical points to trigger the crack were identified. Finally, for the finger shaped cover plate moment connection, considering different loading curves data and in order to present the low cycle fatigue life prediction, displacement versus the number of half cycles diagram is produced.
Finite element results demonstrated acceptable agreement with the experimental data. Furthermore, the low cycle fatigue life of connections under loading with constant amplitude is estimated, and S-N curves are proposed. These curves can be applicable for engineering purposes, such as performance based design. Also it is demonstrated that the finger plate joint revealed a good performance against soft cracking in low cycle fatigue compared to a number of previously tested joints. The results of the S-N curve for a constant displacement loading averaged 73% of the lifetime of the initial cracking. Sensitivity analysis with 20% tolerance on the intrinsic parameters of the micro mechanical model showed a maximum change of 15% in the responses.
 

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The importance of environmental issues has increased the use of biodegradable polymers which nowadays have become among main components in medical and biological applications. In the present study, a new combined method of fused filament fabrication (FFF) and batch foaming was introduced to improve the properties of poly lactic acid. For this purpose, FFF samples were produced with infill percentages of 100, 80 and 60 and then, foamed in batch process. Due to the importance and effect of the void fraction on structural and mechanical performance as well as the biodegradability of materials with porous structure, especially for medical purposes, void fraction and impact strength were evaluated. The results showed that the void fractions of FFF samples were 3%, 13% and 25% in infill percentages of 100, 80 and 60, respectively while after the foaming they reached to 14%, 19% and 30%. The findings revealed that the impact strength of FFF foamed samples was improved compared to FFF solid samples. For samples with 100 infill percentage, the impact strength improved from 207 to 506 J/m² due to the foaming procedure with nano-sized cells created by the batch foaming.

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The condition of non-liability in insurance has been less considered by researchers and existing laws. The ambiguity of the conditions of these terms and  referral of the condition of these terms to the private conditions of the insurance policy, due to the extension of insurance contracts and the superior trading power of insurance companies, is criticized, often to the detriment of the insurers and beneficiaries of the insurance policy Ends. However, according to legal basis, it is possible to cancel the condition of non-responsibility for the main obligation of the insurer, but this ambiguity continues with the insurer's underwriting obligations. Also, in cases where the condition of non-liability is minor, although such a condition is subject to the principal obligation, considering that such a condition does not eliminate the overall effect of the insurance contract, it is not possible to invalidate or insert the insurance contract. But in general, the referral of the status of the condition of non-responsibility to private conditions has created opportonities for misuse. For this reason, reform of existing laws and regulations seems to be necessary from this perspective.
 

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According to the information view, the main function of accounting is to provide information and thus reduce uncertainty. So, the high internal information environment quality (IIEQ) reduces the corporate declared tax disagreement by tax auditors due to facilitating tax planning coordination between different departments of the company and providing documents to tax authorities. The purpose of this study is to investigate the impact of IIEQ on tax risk reduction in listed companies in Tehran Stock Exchange (TSE) by applying data collected from 136 companies during the years 2009 to 2015. For this purpose, the difference between the corporate declared and certain tax due to the uncertainty about the confirmation of the declared tax is taken as a tax risk. The results show that environmental uncertainty increases tax risk. Moreover, income quality, income forecasting accuracy, and financial reporting quality and transparency reduce tax risk. Corporate governance quality, is also effective for tax risk reduction. These findings highlight the importance of environmental conditions, measurement process, financial reporting and internal monitoring for tax risk reduction. On the other hand, based on the research findings, companies with lower tax rates have higher tax risks; but conservatism and asset returns don’t make sense for tax risk. Moreover, tax risk is higher in larger companies, and financial leverage, also, increases tax risk. The findings provide new evidence of the IIEQ impact on the corporate tax planning. These findings can be useful in assessing corporate tax risk based on its IIEQ.

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Under articles 37 and 48 of the United Nations Convention on Contracts for the International Sale of Goods (CISG), the seller is entitled to cure the lack of conformity of the goods due to specific circumstances. The same legal establishment has been accepted in the Article 7-1-4 0f the Unidroit Principles of International Commercial Contracts (UPICC).
Anticipating the seller’s right to cure, one controversial issue raised is the status of the buyer's right to avoidance. Subsequently, the question arisen is whether the seller's right to cure is prior or the buyer's right to avoidance. While there are various interpretations of Article 48 leading to disagreements, in UPICC, the buyer has no right to avoidance in case of seller’s cure under Article 7-1-4. Similarly, according to general principals including Article 478 of the Civil Code in Iranian legal system, the buyer has no right to terminate if the seller is ready to cure.
To conclude, we can say the seller’s right to cure from the perspective of the doctrine, judicial precedent, legal and economic analysis has priority over buyer’s right to avoidance.

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In recent years, advancements in driver assistance technology have significantly minimized the impact of human error on traffic accidents. The development of these systems is of great interest, especially for critical and accident-causing maneuvers such as critical lane change on the highway. One of the important parts of automatic lane change is the motion planning. In this research, taking into account the criteria of collision avoidance and feasibility of the path, an algorithm for the motion planning is proposed. The main innovation of the present research is that the dynamic limits and stability margins of the vehicle have been converted into quantitative criteria and considered in the motion planning. To evaluate the performance of the motion planning algorithm, the complete model of the car is used in the Carsim-Simulink software. Also, to follow the designed path, an integrated longitudinal-lateral control has been designed and implemented. The simulation results show that the proposed method provides a more accurate assessment of the trajectory dynamic feasibility in high-speed critical lane change maneuvers compared to the previous methods. This issue is especially evident for critical maneuvers where the lateral acceleration of the trajectory is more dominant than the longitudinal acceleration.