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In this research, English was instructed to learners with mild intellectual disabilities (IDs) in Iran (2017-2018). In this single-group post-test study, 32 seventh-graders with IDs were selected using convenience sampling. The teaching material was a validated researcher-made pamphlet. Four teachers of special schools instructed the pamphlet for 14 sessions of 45 minutes for four months in the school setting and completed formative assessment forms for each student using descriptive terms. The students’ achievements were compared using the chi-squared test. A significantly higher number of students had a successful performance on listening, reading, and writing compared to those with a relatively successful and unsuccessful performance (p ≤ 0.05), while no significant difference was observed in the case of speaking. Learners with IDs can successfully learn EFL with the aid of methods, techniques, and materials tailored to their needs. Learners with IDs can successfully learn English as a foreign language. Speaking is the most difficult language skill for learners with IDs. The difference in orthographic systems does not affect writing skill development considering the objectives designed in this project. The results encourage foreign learning by learners with IDs and, thereby promoting inclusion.


 

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Jet engines working near the ground, with low speed and high thrust can experience flow separation between ground and inlet which would lead to vortices, called Ground Vortex that have harmful effects on engine performance and can disrupt integrity of inlet flow. Deep understanding of the physics of this phenomenon could omit the injuries of foreign objects damages, engine surge, compressor stall, and fan vibration. In this study, the ground vortex formation near the inlet air duct of an aircraft engine is investigated using computational fluid dynamics. Simulations are performed for a 1:30 scale. The fluid flow is assumed to be compressible, three-dimensional and steady.The k-ω SST model is employed for incorporating turbulent characteristics. After mesh study, the boundary of Vortex or No-Vortex for results of this study compared with a theoretical and an empirical correlation by Murphy which showed good agreement. Moreover, despite free stream existence, decreasing non-dimensional velocity ratio causes the movement of vortex core and by approaching to the critical non-dimensional velocity ratio; the ground vortex would gradually disappear. For U^*= 33,44,66,132 ground vortex is formed, but for U^*=26.4 ground vortex disappears. The computational method has subsequently been applied to configurations that are difficult to test experimentally including headwind flows. According to this study, the formation of the vortical flow field permanently affects the total pressure distortion on the engine fan face. In this paper, DC60 is calculated under headwind condition. These coefficients are 0.39, 0.391, 0.447 and 0.3957 at U^*=33,44,66,132 respectively.