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This paper aims to provide a proper method to calculate the reliability of double curvature arch concrete dam. First pseudo-excitation method for structural analysis was used to calculate stochastic parameters of structure of concrete dam under seismic loading. Then the response surface method (RSM) based on weighted regression was combined with the proposed method of this study to estimate the reliability of the seismic performance of double curvature arch dam. Finally based on a generated series of random data obtained from structural analyses, a random value was employed to calculate the reliability of seismic performance in order to validate the proposed method of this study. Then the proposed method was used to estimate performance reliability of karoon3 located on high seismic zone.

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The high penetration of wind and solar resources and uncertainties in electricity generation from these kinds of DERs may cause problems in the operation of microgrids based on renewable energies and decreases the reliability indices. Implementation of high response generations such as hydro generation is one of the solutions to reduce the uncertainties. This paper presents a method for modeling a microgrid based on hydro, wind and solar generations. Reliability indices of the microgrid are calculated in presence of the lines connecting the microgrid to the upstream network. To demonstrate the effectiveness of the proposed method, detailed simulation results are presented and analyzed for 5 case studies.

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Due  to  increasing  development  of  technology  and  fierce  competitive
environments,  the  most  important  goal  of  decentralized  distribution
networks, which are run by different suppliers, is to maximize revenues
and to increase network reliability. One of the key tools for improving
efficiency  in  the  competitive  environment  is  using  game  theory  and
cooperative games in distribution and transportation networks.
As a matter of fact, the aim of this study is to determine the effective
strategies of cooperative games between suppliers with consideration of
uncertainties in flow parameters, cost and time. The uncertainities are
related to different factors such as, fluctuations in supply and demand,
political  issues,  natural  disasters,  earthquake,  war,  voltage  drop  in
transmission  systems,  and  fluctuations  in  water  distribution  systems.
Therefore,  in  this  study,  two  mathematical  problems  in  certain  and
uncertain  situations  due  to  the  coalitions  of  players  in the  considered
network  are  discussed. Moreover,  reliability  analysis  and  efficient
strategies for  cooperative  games  in  the  form  of  a  case  study  in  water
distribution industry are investigated.

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Nowadays, the evaluation of reliability and availability is one of the most important criteria in all engineering sciences .Due to the increasing of dependency of the life into the electrical energy, the availability of power system is very important for consumers. To achieve this issue, each of the main components of the power system must have adequate reliability. In this paper, reliability evaluation of the pumped storage plants using Markov process is carried out. For this purpose, at first an overview of the structure and the usage of the pumped storage plants is presented. Then, the main concepts of the Markov process model are reviewed and the appropriate model for reliability evaluation of a pumped storage plant is presented. Using the presented model and according to existing equipment, various indicators of reliability and also the possibilities of failure mode, full and half capacity of the plant are reported and sensitivity analysis is carried out to evaluate the effect of repair and failure rates of equipments on reliability of the plant.

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Iran is located an arid and semi-arid region of the world, with an average annual rainfall of less than one-third of the global average. There is lack of water to meet the consumptions in many sectors. The construction of a reservoir on the rivers as an instrument for regulating flow in time and place is one of the ways to deal with the water crisis, , as more than one dam has been built on some rivers. Functional dependence and the impact of the operation of each reservoir on the other one leads to the complexity of the operation of multi reservoir systems. In reservoir operation models, various requirements, such as agriculture, drinking, environmental and hydropower is considered. Multi-objective optimization models are an appropriate tool for dealing with heterogeneous multi-objective problems. MOPSO and NSGA-II are effective multi-objective optimization models that have been considered by many researchers so far. In this research, the comparison of two widely used NSGA-II and MOPSO algorithms to extract the rule curves of Boostan and Golestan reservoirs located in Gorgan Rood watershed in drought conditions has been investigated.

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Generally, the design of dams and other hydraulic structures is carried out based on deterministic approaches. However, there are many uncertainties in the estimation of different effective parameters in hydraulic structures design. The inherent uncertainties in these parameters necessitate reliability analysis to ensure the structure stability. In this study, after investigating various uncertainties in design, the height and overtopping failure of Namrood dam as a case study was calculated based on reliability analysis. For this purpose, the Monte Carlo Simulation Technique that is a well-known method for reliability analysis, was used. Results showed that to get 100% safety from design flood, the height of Namrood dam should be considered as 78.7 m. However, in this case the probability of overtopping failure due to control flood was 64%. Moreover, similar analysis was carried out to investigate the effect of spillway type on overtopping probability of failure. Results showed that by increasing the spillway crest length, the probability of failure in the case of Morning glory spillway increased more rapidly than ogee spillway.

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in the present study, the slope stability coefficient of Namrood dam as a case study was calculated for different load conditions, including permanent leakage and completion of construction by using deteministic and probabilistic methods. Geo-studio software package and Monte Carlo simulation techniques were used for analysis. The effect of earthquake load on the stability of the dam structure was also investigated. The results showed that in the present conditions of the dam, the failure probability of the critical sections of Namrood dam was negligible, so that the maximum probability of failure was calculated as 0.00007. Then, sensitivity analysis were carried out on the value and type of distribution of effective input parameters. Results showed that with the increase in the earthquake load by 15%, the probability of dam failure increased by about 100%. The results also showed that the type of effective parameters distributions including cohesion of soil (c), soil friction angle (φ) and unit weight (γ) have little effect on the probability of dam failure.

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Transformers in power plants act as intermediaries between the power plant and the power grid, which are affected by electrical stresses such as switching, thermal stresses such as overload and arc, and chemical reactions in the dielectric oil. Acid and moisture components cause deterioration of transformer oil and paper insulation. Condition assessment of transformers is a method to predict and prevent spreading of faults in power transformers. The purpose of this paper is to evaluate the health condition of sample transformers of Dez and Karkheh dam hydro power plants using the proposed probabilistic method. The voltage levels of these transformers are 410 and 230 kV and the possible first-order and second-order reliability methods used to determine failure in materials or structures are based on the data of the transformers of Dez and Karkheh dam power plants to determine the reliability assessment. The results are compared and the efficiency of the proposed methods is demonstrated.