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Diversity, accessibility and reliability are the three main factors governing the adoption of information sources by farmers in rural areas. Based on the research hypothesis, the existing knowledge and information delivery system in the agricultural sector, functions far below the ever changing nature and tangible needs of existing farming systems. The main objective in this study is to determine and prioritize farmers’ information channels and their communication networks within rural areas of 19 townships of Isfahan Province – the central part of Iran. After exploratory field visits of several villages, a questionnaire was designed and pre-tested for its validity and reliability (Alpha= 82%). The statistical society included all farmers who had regular contacts with the local extension offices. The sample population was 228 farmers who were selected through a two-step random sampling method from the villages with an extension office. The results showed that extension system disregarded farmers’ local media and did not meet their actual needs. The extension system failed to build trust among the local communities. Moreover, farmers’ trust in one information source had a synergic effect on the others. The sources were categorized in three groups based on the farmers’ preferences. The printed materials did not play any significant role in the knowledge and information processes. There was also a significant correlation between dependent variables (determination of information source by farmers) and the independent variables (for example: farming land size and farmers educational level). Finally, most farmers claimed that visiting ‘local extension service offices’ was mainly in response to their urgent needs to acquire subsidized agricultural input such as fertilizer, rather than acquisition of information and were yet disappointed.

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Numerous models have been proposed to incorporate various equations of state (EOS) into the pseudo potential model. This paper presents an investigation of different EOS types based on the Gong and Cheng model in multiphase-single component flows by the lattice Boltzmann method. Primarily, it is conducted to investigate eight EOS’s classified in four categories; the Shan- Chen EOS, the cubic EOS, the non-cubic EOS, and the cubic and non-cubic combination EOS. The results show that each EOS type results in producing relatively similar spurious currents and has a maximum achievable density ratio. Although by choosing a proper beta parameter for every EOS the simulation errors decrease dramatically, our results show it is impossible to set a constant parameter for the non-cubic EOS. Therefore, a new equation is introduced to predict an efficient beta for the cubic and the Shan- Chen EOS’s. It is also found that the non-cubic, cubic, and non-cubic and cubic combination EOS’s have a wider temperature range and larger density ratios respectively. Hence, we determine a temperature dependent function for the beta parameter prediction instead of using a fixed value for the non-cubic EOS. The results are noticeably in better agreement with those of the Maxwell construction (theoretical results).

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In this research, the use of the exact difference method forcing scheme in the pseudo-potential multiphase model is suggested for the simulation of a droplet impact on a thin liquid film at a density ratio of 1000, and the effect of inertia, surface tension, and gravity forces are considered by means of their corresponding non-dimensional numbers (i.e. the Reynolds, Weber, and Bond numbers). For this reason, the Palabos open source software is modified by implementing the exact difference method in it. The results of our simulations in different Reynolds and Weber numbers show that the Weber number has a slight influence on the crown layer radius, meanwhile, the Reynolds number has a direct effect on the crown radius. The crown height is increased with an increase in the Reynolds and Weber numbers. Furthermore, the comparison between the pseudopotential model simulations and the free-energy model shows that crown shape is related on the surface tension in addition to the non- dimensional numbers and with a noticeable increase in surface tension the crown tip becomes bigger. The influence of the gravity force is investigated through the Bond number. According to the results, the crown height is noticeably affected by the Bond number. When the Bond number decreases, the crown radius and height increase. Therefore, the proposed model with the capability of being used for multiphase problems with large density ratios while producing a low spurious current could be utilized for a vast variety of other multiphase problems as well.