Showing 6 results for zirak
Volume 3, Issue 2 (6-2015)
Abstract
Aim: Health locus of control includes the degree of a person's belief in the fact that his/her health is controlled by internal or external factors. The aim of this study was to determine the status of health locus of control and its related factors among Iranian pilgrims.
Methods: This cross-sectional study was performed on 600 pilgrims of the holy shrines in Tehran in 2015. People aged over 15 years who had come for pilgrimage to the shrines entered the study by convenient sampling and after consent. The A form of the Multi-dimensional Health Locus of Control scale was used. This form consists of Internal Health Locus of Control (IHLC), Powerful others (PHLC) and Chance External Locus of Control (CHLC). The relation of between age, gender, education, income, marital status and location of residence on each construct was evaluated by t-test, ANOVA and linear regression through SPSS21.
Findings: Among the total pilgrims, 302 were females (50.3%). The mean age of the participants was 33.15±11.06 years. The highest and lowest averages were associated with the internal locus of control (25.60±3.34) and the chance locus of control (18.20±5.13), respectively. There was a significant relationship between educational level and IHLC; between income and education level with CHLC; and between marital status and age with PHLC.
Conclusion: According to our results, most people think that they control their health or life events themselves. People with a higher internal locus of control score have more tendency to practice health promotion and disease prevention and seek health through visiting holy sites and appealing to God.
Volume 4, Issue 4 (12-2016)
Abstract
Volume 6, Issue 4 (winter 2018)
Abstract
Abstract “Kalila and Dimna” in Persian literature and “Aesop’s Fables” in ancient Greece are two examples of old works of the world’s literature and are classified as works falling within the domain of “animals allegorical fables”. In the present research, the application of satire as a genre of unserious speech which forms an artistic dimension of the two mentioned books is studied. For this purpose, allegorical narratives of the two books in terms of different techniques for creation of satire such as ethical-critical message, verbal satire, situation satire, specific meanings, characterization and … are studied, compared and clarified. The satire applied in “Aesop’s Fables” primarily focuses on demonstration of existing moral and social contradictions in society by profiting from metaphor and extension in verbal satire and situation satire which of course the brevity in length of fables and application of the brevity technique has helped eloquence and comical aspect of this type of satire. In “Kalilah and Dimnah” too, moral and social contradictions have been given attention to by satirical expression and its narratives’ satirical strength is originated from a variety of themes, characterizations as well as situation satire next to verbal satire, with this difference that in “Kalilah and Dimnah” with composition of Nasrollah Monshi, application of narrative-inside-narrative technique together with descriptions and metaphors and those groups of literally fineries which is characteristic to technical prose, made the narratives lengthy and decreased the effect of satire.
Mohammad Amin Zoljanahi, Saadat zirak,
Volume 16, Issue 2 (4-2016)
Abstract
This article presents a numerical investigation of fluid flow in one of the centrifugal pumps of pump-Iran Corporation. A computational fluid dynamics (CFD) analysis is performed by using the CFX software for a wide range of volumetric flow rates for two different rotor speeds of 1450 rpm and 2900 rpm and the numerical results of water are validated against measured values of head and total efficiency with an overall acceptable agreement. The obtained results have been obtained for crude oil as diagrams of head and total efficiency as the function of volumetric flow rate and other variables and compared with results of water. Numerical results show that the absolute pressure on blade surfaces for crude oil is 705 kpa less than when using water. The absolute pressure difference between inlet and outlet of impeller and spiral volute for crude oil is comparatively less than those amounts in comparison with water. Also by increasing the angular velocity of rotor, it was observed that high levels of turbulence intensity are transmitted from outlet pipe bending to the impeller outlet at volumetric flow rate of 30 m3/h that causes the efficiency reduction and high levels of turbulence intensity for crude oil are less than those amounts in comparison with water within impeller area. Finally, to represent an impeller pump head curve for crude oil over the overall operation range of the pump, a second order polynomial equation was fit to numerical data.
S.m. Hosseini Baghdad Abadi, S. zirak , M. Rajabi Zargar Abadi ,
Volume 19, Issue 1 (January 2019)
Abstract
In this paper, the effect of the angle of injection on the film cooling effectiveness with sinusoidal wave pulsation is investigated at various frequencies. Four angles of injection are selected at 20, 25, 30, and 35 degrees. The pulsed flow is investigated at 3 frequencies of 2, 50, and 500 Hz. Geometry was simulated in Gambit and numerical analysis was done by Fluent software. The SST k-ω model was used for modeling turbulence. The results showed that the injection angle between 20 and 25 degrees in the frequencies studied had the most film cooling effectiveness of the central and lateral line, especially in the areas far from the edge of the hole. Higher frequencies (500 Hz) increase the effectiveness of the film cooling at the lower initial distances of the hole. At far distances, the lower frequency (2 Hz) is the most effectiveness. As the frequency increases, the difference in the cooling efficiency of the central and lateral lines decreases at different angles. As the frequency increases, the interruptions of the flow-off and the flow-on are reduced, and as a result, the instantaneous effectiveness also has a slower variation than the lower frequencies. The blowing ratio of 0.5 had the most value in comparison with the blowing ratio of 0.75 and 1 in all angles and frequencies.
S.m. Hosseini Baghdad Abadi , S. zirak, M. Rajabi Zargar Abadi ,
Volume 20, Issue 2 (February 2020)
Abstract
In this research, the effect of square wave pulsating air on temperature distribution and film cooling effectiveness of flat plate at different frequencies and blowing ratios is experimentally and numerically investigated. Hot air is injected through the holes at an angle of 25 degrees. Square wave pulsed flow is generated at four frequencies of 2, 10, 50, 100 Hz, and five blowing ratios of 0.5, 1, 1.5, 2.4 and 3. To study the film cooling, Navier-Stokes equations are solved by a Reynolds average method. The SST k-ω model was used for turbulent modeling. The results showed that the film cooling effectiveness decreases with increasing of blowing ratio along with an increase in its rate of changes. The difference of centerline film cooling effectiveness between the numerical and experimental values decreases with increasing distance from the edge of injection hole. In general, pulsating decreases film cooling effectiveness in comparison with steady-state. The lift-off of the local jet increases under pulsation. In the pulsating state, the overall film cooling effectiveness decreases by increasing the blowing ratio at a constant frequency. On the other hand, increasing the frequency increases the overall efficiency of film cooling. The maximum averaged centerline effectiveness was obtained at a frequency of 100 Hz and a blowing ratio of 0.5 and the minimum value was obtained for a frequency of 2 Hz and a blowing ratio of 3. For pulsed flow, the maximum and minimum differences of the averaged centerline film cooling effectiveness between experimental and numerical results were 25.55% and 0.717%, respectively.
