فهرست مطالب mohammad reza aminian

One of the most applicable relays in protecting the power system is distance and overcurrent relays. In transmission and distribution networks, protection is usually performed by distance protection, and overcurrent protection is used as a backup for distance protection. In the present study, a new approach was provided to coordinate distance and overcurrent relays using pickup current, time adjustment coefficient, and overcurrent relay characteristics to delay these relays as backup for distance relays. It is possible to adjust the second zone of the distance relays' operating time with a fixed and normal value using instantaneous operation relays with changes in coordination constraints. In the proposed method, the coordination problem was solved using GA algorithm. A protection coordination index is then provided to evaluate distributed generation sources' impact on the protection coordination of distance and overcurrent relays. A new method was proposed to obtain the maximum injection capacity under coordination constraints using MATLAB and DIGSILENT software's parallel performance. The proposed method was implemented in IEEE 9 and 39 bus sample networks. Finally, the obtained results were compared and evaluated.

Nanofluids are new heat transfer fluids, which improve thermal performance while reducing the size of systems. In this study, the numerical domain as a three-dimensional copper mini tube was simulated to study the characteristics of flow and heat transfer of CuO/H2O nanofluid, flowed horizontally within it. The selected model for this study was a two-phase mixture model. The results indicated that nanofluids with the platelet nanoparticles have better thermal performance than other shapes of nanoparticles such as cylindrical, Blade, Brick, and spherical nanoparticles, respectively. By studying the flow characteristics, it was found that the pressure drop and friction factor of the nanofluids are dependent on the shape of the nanoparticles so that the nanofluids containing spherical nanoparticles have the lowest reduction in the friction factor and nanofluids containing platelet-shaped nanoparticles have the highest reduction in friction factor. Furthermore, as new formulas, two correlations were suggested to calculate the Nusselt number of nanofluids according to the effect of nanoparticle shape on the laminar and turbulent flow regimes.

The aim of the study is to investigate the condition of the existing international system and some of the legal dimensions of the humanitarian intervention based on the jurisdiction of states on their natural resources and especially the case of environment and the theories of the diminishing sovereignty of states. It seems that an increase in the power of international organizations and human rights and humanitarian organizations such as United Nations in the practical and theoretical terms, results in the reduction of the absolute and the national level sovereignty of states compared to international behavioral standards. Research question asks whether the Security Council can have humanitarian intervention in the case of environment and consider it a threat to the international peace and security. Through the review of related literature and the collection of information from different sources the researcher concluded that the Security Council will obtain any threat to the peace or its violation and will have some recommendations or will decide to take some actions for the securing or reestablishment of peace and international security based on articles 41 and 42. In fact in the case of the existence of a threat to peace or its violation, based on article 39, the security council based on article 41 can authorize comprehensive economic and weaponry sanctions or based on article 42 resort to military actions. In other words, the actions of the council for the protection of peace and against violations is not considered as intervention. Based on the fact that there are no official references for the evaluation and control of the decisions of the security council, the realization and obtaining the occurrence of a threat to peace or its violation based on article 39 of the Charter is considered the duty of Security Council. Based on article 39 of the Charter, the Security Council has the right to obtain the existence of any threat to peace and international security and ask the parties of the conflict to follow the transitional actions of the council through its own discretion and ask the members of the UN to take necessary actions for the maintenance of international peace and security.