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Rural economy is considered as an economic foundation due to providing food security and essential goods for a country. Therefore, any threat to this type of economy can have many negative consequences on other dimensions of economy. The spread of the Corona Virus has had various effects on the world economy, especially on the rural economy. This research tries to study and analyze the economic effects of the Corona Virus outbreak on the village of Upper Eshkevar. The present research is applied in terms of its goal and is descriptive-analytic in terms of method. The nature of data is quantitative and qualitative and the method of data collection is based on library and field findings. Data analysis is based on future study techniques including interaction analysis. The research findings show that, four main factors including unsustainable employment, unsustainable income, increasing rural poverty and decreasing in investment are in association with COVID-19 effects. Based on t-test and Pearson, it can be said that the economic effects of Corona Virus have averaged 4.44, which shows a significant difference (p> 0.05). It can be said that Corona Virus has had significant effects on the economy of Eshkor Alia village.

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Background: The escalating prevalence of multidrug-resistant (MDR) commensal intestinal bacteria characterized by extended-spectrum β-lactamase (ESBL) production is an alarming global health threat. Drug users have been introduced as a major source of antibiotic-resistant bacteria, possibly due to drug abuse. The present study aimed to investigate the potential factors related to fecal carriage of MDR ESBL-producing intestinal Escherichia coli (E. coli) in drug users in the southwest of Iran.
Materials & Methods: In this cross-sectional study, stool samples of 109 drug users were collected and cultured. After the biochemical confirmation of E. coli isolates, the antimicrobial resistance pattern and ESBL production of the isolates were determined. Then logistic regression analysis was conducted to determine possible factors related to fecal carriage of MDR ESBL-producing intestinal E. coli.
Findings: Logistic regression analysis indicated that increasing age and duration of addiction were associated with increased risk of MDR ESBL-producing E. coli carriage in the intestinal flora of drug users (p< .05). Moreover, oral drug use compared to the smoking method led to a higher carriage rate of MDR ESBL-producing E. coli in the intestinal flora of drug users (p< .05). Also, self-employed drug users compared to those with fixed public occupation showed higher rates of MDR ESBL-producing E. coli carriage in their intestinal flora (p< .05).
Conclusion: Age, duration of addiction, method of drug use, and occupation were significantly associated with MDR ESBL-producing E. coli colonization.

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Nowadays boiling phenomenon has been an important issue in various fields such as petroleum industries and nuclear power plants due to enhancement of the total heat transfer coefficient. One method to increase the level of heat transfer coefficient is to add certain nanoparticles such as 〖Al〗_2 O_3 to the base fluid. The present paper concerns the effect of nanoparticles on forced convective boiling within the general- purpose computational fluid dynamics (CFD) solver FLUENT. The governing equations solved are generalized phase continuity, momentum and energy equations. Wall boiling phenomena are modeled using the baseline mechanistic nucleate boiling model developed in Rensselaer Polytechnic Institute (RPI). To simulate the critical heat flux phenomenon, the RPI model is extended to the departure from nucleate boiling by partitioning wall heat flux to both liquid and vapor phases considering the existence of thin liquid wall film. In addition to validating the subcooled boiling phenomenon, the effect of aluminum oxide 〖Al〗_2 O_3 nanoparticles on heat transfer coefficients has been analyzed. It is concluded that by increasing the volume fraction of 〖Al〗_2 O_3 nanoparticles in the base fluid, wall temperature has been dropped and the heat transfer coefficients have been increased significantly.

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In order to meet increased demand for dissipating high heat fluxes from electronic chips that are continually shrinking in size, development of new cooling technologies have been considered for the last two decades. Recent research efforts have shown that boiling two phase flow through the mini-channels can provide desired heat transfer coefficients. The occurrence of the dryout phenomenon followed by a sudden increase in temperature due to the critical heat flux is one of the most important challenges in this context. In this study, departure from nucleate boiling phenomenon due to the critical heat flux in a mini-channel has been examined using computational fluid dynamics. The governing equations solved are generalized phase continuity, momentum and energy equations. Wall boiling phenomena are modeled using the baseline mechanistic nucleate boiling model developed by Rensselaer Polytechnic Institute (RPI). To simulate the critical heat flux phenomenon, the RPI model is extended to the departure from nucleate boiling (DNB) by partitioning wall heat flux to both liquid and vapor phases considering the existence of thin liquid wall film. It was observed that by applying high heat fluxes near to CHF, DNB occurred and a vapor layer formed adjacent to the wall while most of the flow field is still subcooled liquid.

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Presence of porosity and gas layers around the Al2O3 particles are one of the most important reasons of decreasing in mechanical properties of aluminum metal matrix composites. In this research, for decreasing of porosity, increasing of wettability and uniformly distribution of particles in matrix three method were used; using inert gas for injection powder with 5 liter/ min flow rate, particles heat treatment in 1100 ̊C for 20 min and mill Al2O3 particles with Al particles in ratio of Al / Al2O3= 1. The effect of these parameters on microstructure and mechanical properties of composite were investigated. The results showed that amount of porosity and agglomeration of particles were high in metal matrix composite with handy injection of particles. While injection with inert gas, using heat treatment and Al / Al2O3 milled Cause improve wettability and uniformly distribution of particles in molten Al. the results showed the maximum value of hardness , compression strength and impact energy have obtained in metal matrix composite reinforced with Al / Al2O3 milled with value of 78.7 BHN, 539.1 MPa and 8.2 Joule, respectively.

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Simulation and analysis of two phase flow that crosses over tube bundles is crucial in safety analysis and design of kettle reboilers and steam generators. The geometry complexity of the tube bundle flow field increases the difficulty of the conventional numerical analysis. One of the methods to reduce the numerical calculations cost, is to use the porous media theory instead of the complete tube bundle modeling. Drag and tube bundle resistance force equations have been used in the porous media analysis. Based on available experimental results, two tube bundle arrangements have been considered. Due to existence of symmetric geometry and uniform energy source over the tube bundle, the two dimensional symmetric models has been used as well. It was observed that the predicted pressure drop in this research has acceptable adaptation with the experimental results. Meanwhile, by considering different outlet boundary conditions, calculated void fraction is compared to the experimental results and showed better accuracy than similar CFD research. It was observed that the enhancement of the tube bundle thermal power increases the void fraction in the heating area of the reboiler.

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Steam generators as an interface between first and second loop of light water nuclear power plants is very important in design and safety analysis. Thermo hydraulic analysis can affect the design and operation of a horizontal steam generator using prediction of vapor distribution. In this kind of thermo hydraulic analysis, simulation and study of the tube bundles is crucial in design and safety study of the steam generator two phase flow field. In this research, due to high complexity of the numerical simulation, the tube bundles have been assumed as the porous media. Two phase flow field correlations such as interfacial drag force and tube bundle resistance force have obtained by the equations that have been reported in the similar computational fluid dynamic researches. The heat transfer from primary side fluid to the secondary is calculated three-dimensionally each iteration and is supplied as a heat source on the secondary flow field calculation. Besides porous media flow field validation, decrease of computational domain has been studied using appropriate boundary conditions. It was observed that the computed void fraction compared to the experimental results show better accuracy than similar computational fluid dynamic investigations

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Simulation of the flow around propeller is a complex fluid flow problem, especially when the propeller is closed to free surface. In this study, the effect of immersion depth, advance velocity and the ventilation phenomenon on the performance of a B-Wageningen series propeller close to surface of water have been numerically investigated. For this purpose the ANSYS-FLUENT commercial software has been used to solve the viscous, incompressible and two phase flow field. The rotation of the propeller has been implemented using the rotating reference frame model in steady state and the sliding mesh for unsteady flow. For turbulent flow modeling and free surface simulation, the k-ω SST model and the volume of fluid method have been used, respectively. For validation of numerical results due to lack of access to experimental results of propeller close to surface, numerical solution in open water condition have been performed and performance coefficients have been calculated. Comparing the numerical results with the experiment ones, shows good agreement and confirms results of numerical simulation. The results of the numerical solution show that the submergence ratio and ventilation phenomenon affect the performance of propeller so that by reducing submergence ratio from 2.2 to 1.4 in advance ratio J=0.4, ratio of thrust and torsional moment coefficients to open water performance coefficients reduced to 7.7% and 6%, respectively.

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The use of porous scaffolds for repairing the damaged bone tissues has been increased in recent years. As exploration of the mechanical properties of the scaffolds on the basis of experiments is time consuming and uneconomic, mathematical models are increasingly being introduced into the field, but most of them rely on finite element method and theoretical studies are rarely found in the literature. In this paper, different micromechanical models are presented for obtaining the effective elastic properties of bone scaffolds. Using these models, the mechanical properties of different scaffolds, including ceramic and composite bone scaffolds, are investigated. Single scale and multi-scale modeling approaches are used to simulate the ceramic and composite scaffolds, respectively. Furthermore, because of the wide application of hydroxyapatite in fabrication of bone scaffolds, the mechanical properties of hydroxyapatite scaffolds in different porosities are obtained in the current study by means of the presented methods. Results show that Dewey, self-consistent and differential schemes are the best methods in calculation of the value of Young’s modulus of these scaffolds in porosity ranges of less than 30 %, 30 to 60 % and more than 60 %, respectively. Moreover, self-consistent scheme gives good estimation of the value of Poisson’s ratio of hydroxyapatite scaffolds in different porosities. By obtaining the values of the mechanical properties of the scaffolds in different porosities by these models and using the statistical analysis, the mathematical relationship between the porosity and the mechanical properties of this kind of scaffolds (Young’s modulus and Poisson’s ratio) is obtained.

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Using proper dimensionless coefficients that are insensitive to various operating conditions is a crucial issue during the utilization of a yawmeter probe. These dimensionless coefficients produce the deviation angle of flow, stagnation and static pressures. In the current study, these coefficients are analyzed using SPM analytical and experimental methods. A comparison of experimental and analytical results shows that SPM analytical method predicts the flow deviation coefficients satisfactorily at the operational angle range of three-hole probe. This method also calculates the stagnation pressure coefficient precisely at the deviation angle range of ±10 degrees. The experimental results show that due to the assumption of constant speed on the probe, the analytical method cannot calculate the static pressure accurately. Experimental observations also demonstrate that velocity is increased and pressure is decreased over the probe. This is due to the suction region at the downstream of probe. Unlike analytical results, experimental observations depict that at zero degrees, the flow static pressure is equal to the average of pressure at the left and the right side of probe. Due to sensitivity of dimensionless coefficients of flow static pressure to variation of Reynolds number, various values are reported at different kinds of literature for these coefficients. These coefficients change with Reynolds number variations and their accuracies are decreased. In the current study, a new proper dimensionless coefficient is introduced which represents minimum sensitivity to Reynolds number.

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Importance of manufacturing capabilities for achieving competitive advantage was raised by Skinner. He stated that manufacturing function typically is either a competitive weapon or a corporate millstone. This paradigm set forth by Skinner and refined by scholars who followed him, express that in order to plan successful strategies, managers should pay attention to effects of manufacturing capabilities (Quality, Delivery, Flexibility and cost). Because of trade-off among level of each capability, they should set to the point which has most profitability for the firm. Empirical works of Ferdows, Demeyer and Nakane proceeding The Cumulative Model, this theory suggest that trade-off among capabilities isn’t always feasible, but firms follow a pre-specified order for building manufacturing capabilities as first quality, then dependable delivery, third cost reduction and finally flexibility, where effect of improving each capability on other capabilities could transit to supportive effect. In researches on manufacturing capabilities based on cumulative capabilities theory, effect of innovation is missed, and by studying literature review, we found that innovation can play a key role in creating sustainable competitive advantages. On the other hand, globalization and shorter products and technology life cycle, results in paying a lot more attention to innovation. In our study, we added innovation to the previous model which exists in the field of cumulative capabilities. The aim of this research is to find out the relationship between manufacturing capabilities using structural equation modeling on Saipa Corporation.

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The present tries to study and review the manner the discourse analysis method is being used in family studies. This method especially emphasizes the role of research in the social context. Considering the key role of the family and women and their place in ensuring the prosperity, this sacred institution should be researched upon in this so that we can reveal the structures and processes that are based on ideology and power. However, considering past researches in the field of women and family, a majority of researchers have paid little attention to the social context while investigating those problems. Therefore, it seems a research gap in this field and hence, this article aims to answer to this question: How can family and women's issues be investigated through the discourse analysis method? The influencing factors on this social phenomenon have been written with the aim of determining the type of linguistic strategies in representation, alienation, highlighting, etc. And in the meantime, we will also discuss the evolution of the discourse analysis method. In order to achieve this goal and to understand this matter more easily, we have used the movies Kitab Qanun (Book of Law), Abed and One Day (Forrever and One Day) as examples.