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Hakim Omar Khayyam, the famous Persian poet, is always regarded by many scholars and poets. Khayam has always been preoccupied with issues such as complex secret of existence, life, death, predetermination, and authority, and these issues have wandered him. Sometimes, these issues have drawn him to skeptisism and pessimism, and sometimes, have invited him to gain the opportunity. Mahmud Sami Albarudi, the Egyptian politician and poet, has been inspired by Khayam in such issues as skeptisism to the time, invitation to gain opportunity and enjoyment, and has discussed them. The difference between his philosophy is much narrower than that of Khayam so that he cannot be known as master of a philosophy school. The present study aimed to investigate the roots and signs of Albarudiˊs influence in a comparative view with Khayam. 

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This article seeks to use the descriptive-analytical method and relying on the definitions of social modernism to address the issue of social innovation in the poetry of the two poets and what are the similarities and differences in each of the topics? The analysis of Baroudi's poetry suggests that he is taking advantage of the sophisticated taste as well as following the critics of the West to the affairs of the people and to correct the defects in society. Like Farrokhi Yazdi, he addresses issues such as central justice, homeland, despondency, attention to poverty, opposition to oppression and oppression, and invitation to studying science as one of the most important subjects of his poetry. The most important aspect of Baroudi's and Farrokhi's poetry's differences is that Farrokhi, as a responsible critic, deals more with the community and related issues, but in Baroudi's poetry, he makes imitation of modernization. However, with the advent of the Arab movement and the issue of exile, it is twisted within it and pursues a sharp eye and a sharp sensitivity to the social problems of its country.

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Sour-orange (Citrus aurantium) seed oil was extracted by ultrasound-assisted, heat reflux, and Soxhlet extraction methods and their physical (melting point, viscosity, specific gravity, refractive index, and color) and chemical (acid value, acidity, peroxide value, iodine value, saponification value, and ester value) properties were investigated. Results showed although that some properties of the sour-orange seed oil such as acid value, acidity, peroxide value, iodine value, melting point, viscosity, and color were affected by the extraction method but its other properties such as saponification value, ester value, specific gravity, and refractive index were not affected by extraction method. In addition, the results of this study indicated that the sour- orange seed oil has some advantages such as low free fatty acid, low acid value, low peroxide value, low melting point, high saponification value, and high ester value. Therefore, the sour-orange seed oil can be introduced as suitable edible oil.

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Microwave-assisted hydrodistillation (MAHD) at three levels of microwave power (180, 360, and 540 W) and the traditional hydrodistillation (HD) were applied to obtain essential oils from Bunium persicum Boiss. (Black Zira). MAHD at 540 W started much earlier than that of HD (4 min vs. 38 min, respectively). By the time the extraction of essential oils started with HD, almost 50% of the total essential oils (2.15%, w/w yield) had been extracted with MAHD at 540 W. Analysis of the essential oils using gas chromatography-mass spectrometry showed that γ-terpinene (28.16-31.13%, w/w), cuminaldehyde (24.85-29.20%), ρ-cymene (14.67-16.50%) and limonene (6.13-8.28%) were their main constituents, with a similar composition both after HD and MAHD extraction. The antioxidant activity (reported as IC50) of essential oil extracted by HD was 9.31 mg ml^-1 and those of MAHD at 180, 360, and 540 W were 8.62, 8.79, and 6.45 mg ml^-1, respectively. Microwave irradiation did not cause any adverse effect on the antioxidant activities of the extracted essential oils, therefore, it can be used as a good alternative method to obtain essential oils from B. persicum.

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In this paper, the Flutter analysis of an aircraft wing carrying, elastically, an external store is studied. The wing is considered as a uniform cantilever beam and the external mass is connected to the wing by one spring and damper. The aeroelastic partial governing equations are determined via Hamilton’s variational principle. Also, modified Peter's finite-state aerodynamic model is employed. The resulting partial differential equations are transformed into a set of ordinary differential equations through the assume mode method. Effects of different situations like the wing without external mass, the wing with a rigidly attached external mass, and the wing with an elastically attached external mass on the flutter speed and frequency are investigated. The numerical results for a wing are compared with published results and good agreement is observed. Then, Simulation results for the wing with an elastically attached external mass are presented to show the effects of the wing sweep angle, store mass and its location and the spring rigidity constant on the wing flutter. Results show that sliding the external mass toward the wing tip in spanwise direction and also toward the trailing edge in chordwise direction decreases the flutter speed. Furthermore, increasing the store mass and spring constant decreases the wing flutter speed. Results show that increasing the wing sweep angle, increases the flutter speed, in all situations.

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In recent decades, study of the behavior of ship motion in waves is considered by researchers. In this paper, mathematical modeling of nonlinear coupling of roll and heave modes of a ship under harmonic excitation in heave direction is studied. The method of multiple scales is used to solve nonlinear equations. Equations of motion in harmonic excitation is studied. In order to validate the responses obtained by the method of multiple scales, the response obtained for a sample is compared with the numerical solution of the equation and good agreement is obtained. Analysis ship motion requires time consuming computations in large scaled model. In addition to evalution of nonlinear coupling roll motion with heave in forced vibrations, the motion is modeled with a simple mechanical system includes mass–spring-damper and pendulum under identical conditions and the response of equal system with response of the original system is consistent. Sensitivity analysis was carried out for nonlinear coupling of roll and heave in harmonic excitation with local and partial derivative methods and the results from two methods is compared.

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In this paper, equations of motion for a horizontal axis wind turbine with movable base are extracted and natural frequencies and vibration of the system is studied. The wind turbine tower is assumed rigid while its blades are modeled as flexible beams. In-plane bending and twisting are considered as two degrees of freedom for blades motion.The shaft connected the tower to blades is assumed rigid and its rotational velocity is considered.In this paper, specifically, a 5-megawattfloating horizontal axis wind turbine, which it’s basehas three angular velocities in different directions,is studied.Due to the complex shape and variation of the properties along the length, the turbine blade properties such as mass and geometric parameters are extracted by curve fitting in MATLAB.The equations of motion and boundary conditions are derived by Hamilton's principle and then are transformed to ordinary differential equations by Galerkin method. By setting the governing equations to standard form (space state), eigenvalues and frequencies are calculated. The numerical results are compared with published results and good agreement is observed.Then the effect of various parameters on turbine blades frequencies and time responses are demonstrated. Results show that the tower base angular velocity and blades rotational speed have considerable effects on turbine blades time response and vibration frequencies.

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In this study, the inverse heat transfer problem of the estimation of unknown heat flux imposed on the boundary of a one-dimensional slab is solved by the genetic algorithm and two modified versions of this algorithm and the results obtained from different versions of the genetic algorithm are compared with each other. These two modified versions are developed based upon genes rearrangement approach. In this approach, an additional cost function is added to the conventional genetic algorithm to increase its computational efficiency. The results obtained by using errorless simulated temperature measurements show that modified genetic algorithms can improve the convergence and accuracy of the inverse solution in comparison with the conventional genetic algorithm and they give accurate estimations for the supposed heat flux even by using a small number of generations and moderate population size. The results show that modified genetic algorithm (2) provides better response to all the parameters of the solution evaluation in comparison with the conventional genetic algorithm and other modified version. In addition, in this study, the effect of adding Tikhonov regularization term to the objective function on the stability of the solution is investigated. Although only a simple one-dimensional problem has been solved in this study to demonstrate the approach of genes rearrangement, but this approach is expected to succeed in the inverse solution of complicated multidimensional problems.

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With the recognition of wind energy in the world, wind farms are expected to become more extended and cover increasingly larger surface areas. The most important issue in large wind farms is increasing power and efficiency. When wind turbines are deployed in large arrays, their efficiency decreases due to complex interactions among themselves and with the atmospheric boundary layer (ABL). When the length of the wind farms exceeds the height of the ABL by over an order of magnitude, a “fully developed” flow regime can be established. Since the length of the farm is larger than the atmospheric boundary layer thickness, changes in the streamwise direction can be neglected and the relevant exchanges occur in the vertical direction. In the wind farms established in the fully developed atmospheric boundary layer, the kinetic energy extracted by the wind turbines is transported into the wind-turbine region by vertical fluxes associated with turbulence. Surface roughness is one of the most important factors affecting this phenomenon. In this research, the effect of surface roughness on the efficiency of the large wind farm in the ABL by large eddy simulation is investigated. For this purpose, the large eddy simulation (LES) is applied to solve the turbulence flow equations. In this article wind turbines are modeled using the classical drag disk. The various surface roughnesses are modeled by logarithmic wall functions applied to the bottom of the domain. The results show that the efficiency and power of the wind farm are decreased by increase of surface roughness.

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In this paper, the performance of a typical 190 W photovoltaic cell, located in Research Institute of Petroleum Industry, Tehran, Iran, has been studied and evaluated from the energy and exergy point of view. A computer code has been developed for modeling and determining the electrical characteristics of the system such as open circuit voltage, short circuit current, system resistances, maximum power point properties and characteristic curves. The operational and electrical parameters of the system and the environmental conditions such as solar radiation, wind speed and ambient temperature have been experimentally measured and logged on one typical day of May. For the validation of model, the results obtained from the model have been compared with the data reported by the manufacturer as well as the experimental data. The results show that the energy efficiency varies from 11.22 to 13.94 percent during the study period (7:30 AM to 5:30 PM) and its average is equal to 13.19 percent. The exergy efficiency also varies from 14.77 to 16.66 percent during the study period and its average is 15.62 percent.

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In this article, the effect of using phase change materials to improve heat transfer in power distribution transformers has been investigated experimentally. To enhance the cooling of the transformer, a new method has been proposed, which involves adding paraffin inside aluminium containers that are sealed to the transformer oil. The test setup includes an electric transformer filled with transformer oil, two electrical heaters, a power regulator, a thermal camera, oil insulation measuring device, and temperature sensors placed at various locations. The experimental results demonstrated that the addition of phase change materials to the electronic transformer oil led to a decrease in the temperature of the transformer, particularly in summer weather conditions. Additionally, the mean temperature of the transformer oil was reduced from 46.7 to 42.5 degrees Celsius by adding 8 kg of paraffin. However, it was observed that when the temperature increases suddenly and rapidly within an hour, these materials are ineffective in dissipating the heat and reducing the temperature of the transformers. Additionally, the research examines the impact of continuous and high-temperature increases on the oil electrical insulation. The results revealed that using phase change materials increased the voltage that the oil could withstand as an electrical insulator from 56.8 kV to 61 kV.