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The optimal implementation of Computer Assisted Language Learning (CALL) in Iranian EFL higher education faces some challenges despite its incremental growth. It is, therefore, necessary to investigate the current challenges affecting university professors' and students' adoption of CALL in Iranian EFL contexts. For this purpose, data were collected through semi-structured interviews with three purposeful sampling groups of participants, both before and after the temporary shutdown of the educational sector due to COVID-19 spread. Therefore, 33 interviewees—university EFL professors, students, and Information Technology Support Engineers (IT-SE)— took part in an interview which took approximately 90 minutes for each, conducted in person or over WhatsApp and Skype platforms. All the interviews were audio recorded and transcribed for thematic analysis by the first researcher and an assistant researcher. The obtained results highlighted nine major categories of themes that indicated the obstacles and challenges of optimal CALL implementation. These challenges are related to 1) technological dimension, 2) teacher dimension 3) student dimension, 4) software and hardware dimension, 5) sanctions and filtering dimension, 6) curriculum dimension, 7) the nature of e-learning dimension, 8) socioeconomic and cultural dimension, and 9) university administrators' dimension.  It was the sanctions and filtering dimension, the nature of e-learning dimension, and the socioeconomic dimension that were exclusive to this study. Each of these major themes includes a set of minor themes. The results can contribute to educational planners, curriculum and material developers, and teachers to develop education programs for optimal CALL implementation in Iranian EFL higher education by removing the challenges.
 

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This study was conducted in order to determine the situation and position of Jetstream in the west of Iran and its speed during the rainy synoptic systems in land surface. Therefore, rainfall data of sven synoptic stations in Ilam and Kermanshah provinces during the 1990s, and 60 systems were selected and of the accessible systems the maps 54 were analyzed. The required analyses were carried out by assessing maps on two days before precipitation, beginning of the precipitation day and the days of maximum precipitation. The results showed that Jetstream tracks had anticyclonic curve two days before precipitation which acquire cyclonic curve on the beginning of of precipitation day and the days of maximum precipitation. The value of the Jetstreams meridian gradient is much more, on the days of maximum precipitation than the other days and falls to the minimum rate on the days before precipitation. Jetstream cores were spread on two days before precipitation too which were concentrated in two areas on the beginning and on the maximum precipitation days. The first area was placed in 25-30° north latitude and 32.5-42.5° east longitude (Northern Red Sea) and the second area in 35-39° north latitude and 45-50° north longitude (Southeastern Caspian Sea). There was no linear correlation between Jetstream cores velocity and the volume of system precipitation, because of the effect of many factors on the amount of the systems, precipitation amount. The maximum effect of Jetstream in the studied area was when the Jetstream in the upper levels of troposphere (200 hp) was place of in the south of the lower levels of the Jetstream (300 hp), so that the Jetstream in the lower levels of troposphere was closer to the studied area.

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Effects of various fertilizers such as farmyard manure (FM), urea, and plant growth promoting rhizobacteria (PGPR, including the genera Azotobacter and Azospirillium) were checked on yield, fatty acids, protein, and oil contents of sunflower. A two-year field experiment was conducted in a semi-arid region in Iran in 2007 and 2008. The experiment was a split plot in a randomized complete block design with three replicates, with five fertilizer treatments as the main plots and two PGPR treatments as sub plots. Results demonstrated that the integrated fertilizers significantly increased the leaf area index, plant height, grain production, biomass, oil yield, and protein content in comparison with organic or chemical fertilizers. The maximum and minimum oil contents were obtained by applying 100% farmyard manure (F1) and 50% FM + 50% chemical (F3), respectively; however, opposite results were observed for protein content. When higher FM rates were used with PGPR, the saturated fatty acids (palmetic and stearic acids) declined significantly, while unsaturated ones (linoleic and oleic acids) were increased. The highest contents of linoleic acid (52.6%) and oleic acid (39.8%) were observed in F₃ and F₁ treatments, respectively. Bacterial inoculation also increased the leaf area index, plant height, biomass, grain and oil yields, oil and protein contents up to 12, 3.7, 7.8, 10, 6.5, 5.6 and 5%, respectively.

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Composites are widely being used due to their good properties such as high strength to weigh ratio, stiffness, resistance to buckling and fatigue, and etc. in different industries. Parabeam three-dimensional composites have found a remarkable situation due to their high bending strength and extremely low weight compared to other sandwich composites. Drilling is necessary to connect them to other structures. In this research, the effects of rotational speed, feed rate and tool diameter have been studied on the amount of damage in drilling of 3D composites. A full-factorial design of experiments was used to assess the significance of drilling parameters, and digital photography technique with auto focus was used to evaluate the damages from drilling. . The drilling operation was assessed based on two introduced factors including the matrix fracture factor (MFF) and uncut fiber factor (UCFF). The analysis of experimental results showed that among the main Parameters, Feed rate and rotational speed, have highest and lowest impact on MFF by 23.83% and 0.34%, respectively. But the experimental results for UCFF showed tool diameter with 17.17% is the most effective parameter. Both factors have similar behavior against the rotational speed which has the least impact on the output parameter. Rotational speed of 1750 rpm, feed rate of 0.1 mm/rev, and tool diameter of 10 mm were found to be optimal levels to obtain the minimum MFF and UCFF.

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Selecting tool materials, tool sizes and determining the cutting parameters presents a great challenge in machining operations especially in high speed machining processes. In this study effect of feed rate which is one of the important machining parameters and tool size on tool life in high speed machining of Ti-6Al-4V alloy were investigated. Fixed cutting speed of 200 m/min, feed rate of 0.03 and 0.06 mm/tooth together with axial cutting depth of cut 5.0 mm, and radial cutting depth of cut 1.5 mm were employed as the cutting parameters. TiAlN + TiN coated tungsten cemented carbide insert in two different size was used during machining operations. Flank wear land measurement was taken by using a toolmakers’ microscope and recorded accordingly throughout machining processes. The results showed during the machining employing both feed rate and using smaller tool size chipping occurred on the tool nose along with gradual tool flank wear. Also by increasing the feed rates utilizing the smaller size of tool highly affected tool life compared to employing the larger one during the high speed machining operations. Reduction the feed rate by 50 percent increased the tool life of smaller tool size by 200 percent.

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Underground water is an important source for drinking and agriculture in the worlds. Due to Extraction of these resources and too frequent droughts in recent years the level of resources has been a significant drop. The aim of this study was to investigate the impact of drought on groundwater levels and estimate the time lag of drought in Plain of Darab. To do this, using rainfall data of Darb ghale darab Station and climate index SPI was extracted conditions of drought. And trend by using the Mann - Kendall non-parametric test was analysis. Then hydrograph of ground water level from 71 to 89 years by using the arithmetic mean of 42 wells was plotted. Finally, by using Mann - Kendall test, trend of 19-year ground water level data of the study area was given analysis. The results indicate that the region Experience of drought during this time and rainfall has been decreased. Analysis of 42 wells showed that the decline in groundwater levels in 40 wells has increased and two other wells, one of them had fixed trend, and other has been reduced in the drop rate. And results of correlation in precipitation data and drop in Groundwater Level showed that the decline in groundwater levels than precipitation occurs with 5 months lag.

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Today, polyether ether ketone composites are widely used in the medical and aerospace industries due to their high strength-to-weight ratio, anti-allergic properties, high buckling resistance and fatigue. Grinding has a high specific energy among traditional cutting processes. Usually a high portion of energy will converts to heat. Because heat has an important role in polymer grinding, the heat modeling of it is necessary. In addition to the energy of chip formation during material removal, there are other energies such as plowing and friction energy. The contribution of each of these energies affects the efficiency of the process. By theoretical calculating of the cutting energy and comparing it with the experimental specific grinding energy, the portion of chip formation energy versus friction and plowing energy can be calculated. By performing differential scanning calorimetry test and theoretical calculations, the amount of chip formation energy was 0.089 and 0.119 J/mm^3 for GFRP and CFRP, respectively. While the experimental results of grinding showed a minimum specific energy of 2.2 J/mm^3 and 2.4 J/mm^3 for GFRP and CFRP, respectively. This difference indicates the very high portion of plowing energy in the grinding of this material and especially polymeric materials. The percentage of the chip-forming energy that enters the workpiece as heat was calculated to be 27%. Therefore, it can be stated that all energy except 73% of the chip formation energy enters the workpiece.