masoud rahimi

In this study, the performance of various types of bladeless wind turbines and eddy formations are evaluated by CFD modeling. At first, a two-dimensional cylinder oscillation is simulated at Re = 51600. The results showed that the oscillation began in 0.2 seconds and that the system's oscillation and full eddy flow formed in 0.9 seconds. With a natural frequency of 2 Hz, it is also noted that the displacement range, flow velocity, and lift coefficient variations fall within the ranges of 0.8, 1-2, and 1-1.5, respectively. Secondly, four types of geometries, including circle, half-circle, half-circle-triangle, and half-circle-rectangle, are designed, and two-dimensional simulation is performed for these geometries. Significant parameters have been examined, including transversal displacement values, force drag and lift coefficients, and the vortex flow pattern formed behind these objects. It is discovered that the half-circle-triangle form has the lowest number of displacement vibrations and the maximum values of the displacement range height, velocity of the flow, and lift coefficient. The half-circle-rectangular shape had the highest frequency with a value of 5.75 Hz in comparison with the other geometries. Also, by examining the parameters mentioned in the half-circle-rectangle shape, it is found that for different Reynolds numbers, the largest response of the displacement range occurred at the lower Reynolds number, and that is the reason why the range response becomes weaker as the Reynolds number increases.

River morphology holds significant importance in the fields of geomorphology and river management and engineering. The marginal sections of rivers have consistently undergone changes in their riverbeds due to various social and economic factors. The Dare Ourt River, located in the Ardabil province, represents a permanent river that has experienced frequent floods and alterations in its channel morphology in recent periods. In this study, the Dare Ourt river was thoroughly analyzed using the Rosegen model at levels one and two. To conduct this study effectively, detaied data such as 1:2000 river topographic maps, hydrometric data, and boundary conditions from the Ardabil Regional Water Authority were collected and utilized. Furthermore, the HEC-RAS hydrodynamic model was employed to extract the primary indices of the Rosegen model with greater accuracy. The outcomes revealed that the majority of the river sections exhibit a C6c type, characterized by an alluvial substrate. Additionally, other dominant types observed within the four examined ranges include B6c, E6b, F6, and D. Field visits also confirmed a transition in the river type from C to F within range 4, which presents challenges for the reconstruction and restoration of the river in type F. As a recommendation, it is advised to implement restrictions to prevent the river from transitioning into type F.

Rockfalls are a type of slope movement process that does not require a transporting medium (e.g., water) and predominantly occur under the influence of gravity (Dikau, 2006). The detachment of a single rock block or a volume of blocks from steep slopes is followed by motions mainly through the air. The fall trajectory is strongly controlled by the mean slope gradient, enabling different motion modes such as free-falling, bouncing, and rolling. Consequently, rockfalls present an unpredictable threat, especially along highways and railways, where they can cause damage to infrastructure or endanger human lives (Bostjančić et al., 2020). In high mountain regions, rockfall activity is thought to be changing due to accelerated climate warming and permafrost degradation, potentially resulting in increased activity and larger volumes involved in individual falls (Stoffel et al., 2024). Therefore, it is crucial to assess areas prone to rockfalls in mountainous regions. The aim of this research is to zone the risk of rockfalls long the Khalkhal–Shahroud road using a multi-layer perceptron algorithm.

The multi-layer perceptron algorithm is a modern machine learning model capable of solving complex problems. In this study, the necessary data were obtained from topographic maps at a scale of 1:25,000, geological maps at a scale of 1:100,000, a digital elevation model (DEM) with 12.5-meter resolution from the ALOS-PALSAR satellite, Sentinel data (spatial resolution of 10 meters), Google Earth satellite images, and field studies. In rockfall hazard zoning using GIS, the most critical component is the preparation of a rockfall distribution map or rockfall inventory. Fieldwork was conducted to identify rockfalls and prepare the inventory.

To identify the factors contributing to rockfall occurrence, field studies identified eight key factors: elevation, vegetation, slope aspect, distance from faults, distance from roads, geology, land use, and slope gradient. After pre-processing, all layers were entered into SPSS Modeler software, and the model was designed with 8 input neurons, 8 intermediate neurons, and 1 output neuron. The results revealed that, in the multi-layer perceptron algorithm, the geological layer had the highest weight value (0.20), followed by the land use layer (0.14) and distance from roads (0.12). In the model validation phase, the results demonstrated an AUC value of 0.9810 in the training phase and 0.9876 in the testing phase, indicating high model validity in both phases.

Conclusion:

This research aimed to identify areas at risk of rockfall along the Khalkhal–Shahroud road using a multi-layer perceptron algorithm. The results highlight the significant influence of geological conditions on rockfall occurrences, emphasizing the need to consider slope instability in all spatial planning efforts in this region. It is recommended that future studies explore other machine learning models, such as support vector machines, to further evaluate rockfalls and related slope movements.

Avalanche is the fast and downward movement of large masses of snow and avalanches can endanger human lives and cause huge financial losses. Therefore, zoning and evaluating areas prone to avalanches is one of the necessities of environmental planning to prevent crises and The reduction of human and financial losses in different regions. The connection road between Khalkhal and Shahrood sector has attracted special attention due to the development of the communication network in the region and its economic, tourism, and transit importance. This route is located in a mountainous area with special geomorphic and geological conditions, and the occurrence of avalanches in this area has caused many human and financial losses every year. For this reason, the evaluation and zoning of avalanche-prone areas on the Khalkhal Road to the Shahrood section is very important.One of the most basic stages of conducting any research is collecting data and information. In this research, various data and information have been used, including a geological map of Ardabil province with a scale of 1.250000, from which the information about faults was extracted, topographic map of Khalkhal. With a scale of 1/20000, the road map is extracted from this map, the field data of the avalanche points has been collected through the field survey and GPS device, and the important remote sensing data and information include vegetation, land use, elevation map, slope map, slope direction map It was calculated from the images of Sentinel 2 and ALOS-PALSAR satellites. This research is based on field, analytical, and statistical works. Arc GIS, SPSS Modeler, and ENVI software were used to prepare the layers and implement the research model.According to field studies and analysis of satellite images to identify factors affecting avalanches on the road from Khalkhal to Shahrood, 8 layers in order: 1- Height 2- Vegetation 3- Slope direction 4- Distance from the fault 5- Distance from the road 6- Snow area 7- Land use 8- Slope was used with the standard raster format and all the layers were collected together after production and a single raster image was created. After finishing the classification process, modeling was done in SPSS Modeler software with 8 input neurons, 8 intermediate neurons and 1 output, and 70% of the data were allocated for model training and 30% of the data for model testing. The type of algorithm of SVM and MLP model is after error propagation. At the same time, this algorithm is very efficient and makes the model learn as well as possible, and the model process is completed when the minimum amount of error is reached.The results show that in the support vector machine model, the highest weight value for the snow layer is 0.26 and for the slope layer and the distance from the road is 0.18 and 0.15, respectively, which indicates that avalanches and hazards It is more dependent on these variables. Also, in the multi-layer perceptron model, the highest weight value was assigned to the snow area factor with a value of 0.20, followed by the layers of the distance from the road, both values of 0.17 and 0.13.Also the area of risk classes shows that in the support vector machine model, the most class in terms of risk is 36.34 square kilometers and in the multi-layer perceptron model it is 45.83 square kilometers, which shows that the multi-layer perceptron model is better than the volume vector machine model. A large part of the area is classified as high-risk class. Also, in the support vector machine model, the value of 61.57 square kilometers for the high-risk class and 49.32 square kilometers for the multi-layer perceptron model is classified, which shows that there is a big difference between the area values of the models that the support vector machine model had a realistic performance and was able to correctly identify the areas where there was an avalanche process and the risks arising from it, while the multilayer perceptron model did not have a good performance in the high-risk section. In the medium risk section, the results of the gear mark area values are that the support vector machine model with an area of 23.93 and the multilayer perceptron model with a value of 25.83 square kilometers are classified and there is not much difference between the values of the areas, but in the low risk category, the multilayer perceptron model with The area of 15.73 square kilometers is slightly different from the area of the support vector machine model with an area of 14.87 square kilometers.According to the results of two models regarding avalanche risk zoning in Khalkhal axis to Shahroud, also according to the mechanism of avalanche and the risks arising from it, it has been found out by field studies that the morphology of the slopes overlooking the road, the slopes of the central part in the area of Eskistan village due to the angle A slope of 20 to 35% and too close to the sacred road with snow and its accumulation during the winter seasons with the least mobility causes avalanches. The occurrence of avalanches in the region is in the form of slides and masses and does not have a powder state, because the length of the range and also the road factor have a great impact on the occurrence of this avalanche model. The cause of this provocation is known to be the avalanche. The results of the support vector machine model with relatively few deviations from the multi-layer perceptron model have high reliability and have been able to identify dangerous areas well. . Also, the overlap of the identified areas with real points is high in both models, but the results related to the identification of avalanche-prone areas in the support vector machine model have better performance than the multilayer perceptron and can identify the areas realistically and carefully. Therefore, both of these models can be used to identify areas prone to avalanches.

Generally, gas is known as the main source of energy. In the industry, a lot of energy is used to increase the power of the heaters in the pressure reduction stations. Therefore, in this study, in order to increase the speed of the heat transfer rate in the heaters of the pressure reduction station, parts with special angles (classic twisted tape) have been embedded in the coils. The above study was carried out on the heater of CGS & TBS pressure reduction station of Maviyan (Kamiaran city, Kurdistan province) with a capacity of 2500 2500 m3/h. In this regard, different temperature conditions of the water heater have been carefully investigated. On the other hand, three classic twisted tape with three different steps had been designed. In all models, the length of the classic twisted tape is 200 cm, and the height is 3.8 cm. The length of each step in the first model is 8 cm, the second model is 6 cm, and in the third model is 4 cm. The results shows that the maximum percentage of heat transfer improvement using the classic twisted tape with the third structure in a water temperature of 35º Celsius is 16%. On the other hand, the minimum percentage of heat transfer improvement in the classic twisted tape with the first structure at 60° Celsius is about 3.82%. These results can be effective and practical for increasing heat transfer efficiency and reducing conversion costs.

To describe delayed‑onset infectious endophthalmitis 4 months after intravitreal aflibercept injection.

An 80‑year‑old female was referred with signs and symptoms of clinical endophthalmitis 4 months after intravitreal injection of aflibercept for choroidal neovascularization. Noninfectious causes of panuveitis were excluded and she was diagnosed with delayed‑onset postinjection infectious endophthalmitis. Vitreous and aqueous specimens were prepared and antibiotics (vancomycin and ceftazidime) were injected intravitreally.

Vitreous culture was positive for Staphylococcus epidermidis. During the 1st month after the antibiotic injections, symptoms and signs of the patient improved and became stable during the 6‑month follow‑ups.

Delayed‑onset infectious endophthalmitis can be presented following intravitreal injections. Late presentation of uveitis in postinjected eyes needs complete investigations to rule out infectious endophthalmitis as an ophthalmic emergency.

Fumarate-alumoxane nanoparticles (Fum-ANPs) incorporated PES nanofiltration membrane was fabricated via phase inversion to achieve favorable performance as the enhancement in the dye removal and antifouling capacity. FTIR spectra of the Fum-ANPs revealed that the carboxylate and hydroxyl functional groups were created on the surface of Fum-ANPs. The strong affinity of Fum-ANPs functional groups with water molecules made the membrane surface more hydrophilic. Hence, the modified membrane sample had a higher pure water flux than the bare one. Zeta potential data showed that the Fum-ANPs blended PES membrane was negatively charged at a pH value of 6, which is favorable for negatively charged solute rejection. The antifouling behavior of the membranes was analyzed using powder milk solution (8 g/L) in a dead-end filtration system. The obtained results demonstrated that the introduction of Fum-ANPs in the membrane matrix ameliorated the antifouling behavior of the resulting membrane. To further study the performance of the Fum-ANPs incorporated PES membrane, removal of Direct red 16 dye was tested. The removal efficiency of Direct red 16 with the Fum-ANPs blended PES membrane was 99% while it was 88.2% for the bare membrane sample.

To evaluate the incidence of unplanned return to the operating room following vitreoretinal surgery and assess the reasons.

In this retrospective case series, medical records of all patients who underwent vitreoretinal surgery were reviewed to determine the incidence and reasons of early (<30 days postoperatively) and late (≥30 days postoperatively) unplanned reoperations after the surgery.

A total of 488 eyes of 468 patients with a mean age of 55.84 ± 18.23 years were included. Fourteen percent (68/488) of eyes required one or more unplanned reoperation following their primary surgery. These include 3.9% (19/488) for the early and 10.0% (49/488) for the late reoperation. The most common primary reason for baseline surgery was rhegmatogenous retinal detachment (RRD) without proliferative vitreoretinopathy (PVR, 38.2%), followed by RD with PVR (23.5%), and tractional RD (TRD, 19.1%). Unplanned reoperations were most common in RD with PVR (19.3%), RRD without PVR (17.2%), and TRD (14.4%). Overall, the most common reasons of the first unplanned reoperation were repeated RD with PVR (27.9%), repeated RD (19.1%), and the presence of silicone oil (SO) in the anterior chamber (AC) (10.3%). For early unplanned reoperations, SO in AC, postoperative endophthalmitis, and persistent hyphema were the most common causes. Repeated RD with PVR was the most prevalent cause of late unplanned reoperations (34.7%). In the multivariate analysis, preoperative best‑corrected visual acuity (BCVA) was significantly lower in eyes with unplanned reoperation than in eyes without (P = 0.011).

Unplanned reoperation following vitreoretinal surgery is not very common, and occurs mostly in the setting of PVR, RRD, and TRD. Lower preoperative BCVA may indicate an increased chance of future unplanned reoperation(s).

Today, people live in a digital world and everyone from children to adults is able to master technology in the form of computers and gadgets. In recent years, the use of gamification has been an important focus of attention in English as foreign language learning. This study aimed to examine the influence of using mobile games on the vocabulary improvement of young learners. A mix- quasi-experimental pre-test – post-test design was implemented in which 30 male and female young learners studying English as a foreign language at Iran Language Institute in Kermanshah were participated. The quantitative data was analyzed using the independent samples t-test. The qualitative data was gathered through interviews and analyzed using Maxqudia software. The results indicated a statistically significant difference between the control and experimental groups in terms of vocabulary achievement. The experimental group performed better and achieved higher results compared to the control group. However, it was found that there was no statistically significant difference between male and female students regarding their improvement in vocabulary. The results of qualitative part indicated that both male and female students exhibited a positive attitude towards the use of mobile games. The participants expressed interest, enthusiasm, and motivation while playing the mobile games. They displayed a keen desire to expand their vocabulary knowledge and acquire new words. Moreover, the mobile games facilitated easier memorization of the words. The findings of this study can be useful in language education.

Accurate and fast estimation of maximal oxygen uptake (VO2max) as an indicator of cardio-respiratory fitness (CRF) by regression equations without exercise tests in large populations is of great importance in the field of health and sport sciences. Therefore, the aim of this study was to evaluate the cross-validation of the non-native non-exercise (N-EX) regression equations in estimating VO2max of healthy and adolescent boys using the standard method of respiratory gas analysis.

This research was a cross-sectional study in which 349 healthy boys children and adolescents (age: 12.49±2.72 year, BMI: 20.13±4.70 kg/m2 and VO2max: 41.50±6.47 ml/kg/min) were participated. VO2max was measured on a treadmill by the respiratory gas analysis in modified Bruce exercise test (criterion method) and then estimated by three non-native N-EX regression equations. To evaluate the cross-validation the validity of the N-EX regression equations, Pearson correlation, paired sample t-test and Bland-Altman agreement were used for extraction of results.

A significant correlation was observed between VO2max measured by criterion method and N-EX equations (R=0.63 - 0.73, p<0.01). However, a significant difference (p<0.01) was observed between VO2max of criterion method and predicted VO2max by N-EX regression equations (mean difference=6.4–11.69 ml/ kg/min). Also, the Bland-Altman plot showed low agreement between measured and predicted VO2max.

The nonnative N-EX regression equations studied in the present research do not have the necessary accuracy to estimate the VO2max of in healthy children and adolescent boys. Therefore, it seems necessary to verify foreign N-EX VO2max regression equations before use in the Iranian population.

The use of seeds to create genetic mutation brings problems because the use of seeds increases the duration of the research, and the study of traits requires plant cultivation, making it impossible to test more than once a year. Another point is the presence of shimmer in mutant plants. Biotechnology techniques, especially tissue culture, solve these problems today. In this method, a repeatable and efficient regeneration system is needed to create mutations in rice plants to obtain fertile plants from the changed tissues.

To determine the appropriate dose of mutation induction to create genetic changes in the callus tissue obtained from the mature and immature embryos of Nemat and Taram rice varieties, a factorial experiment was carried out within a completely randomized design using doses of 20, 30, 40, 50 and 60 Gy (GY) of Gamma radiation in four replications. For callus generation, MS medium with 0.5 mg/liter 2, 4-D and 1 mg/liter Kasein was suitable for both cultivars. Also, for the regeneration of calluses obtained from both types of embryos of the Tarom cultivar, MS base medium containing 4 mg/liter of BAP, 0.5 mg/liter of IAA, 0.5 mg/liter of NAA, and 5 mg/liter of Kasien were used. In the final stage, 30-day-old calluses were subjected to gamma radiation treatment with five doses of 20, 30, 40, 50 and 60 Gy. They were compared with the control treatment in the regeneration stage regarding moisture percentage, growth rate and regeneration percentage.

After irradiation, the effect of variety on regeneration percentage, growth rate based on weight and callus diameter, the effect of embryo type on regeneration percentage and moisture percentage, the effect of radiation on all studied traits, the effect of variety × embryo only for regeneration percentage and moisture percentage, the effect of variety × radiation for all traits and the effect of embryo × radiation and cultivar × embryo × radiation were significant only for the percentage of reproduction. The LD50 obtained in Nemat and Tarom cultivars with mature embryos was related to doses of 26.78 and 41.83 Gray, respectively; with immature embryos, it was 14.55 and 35.30 Gray, respectively.

The difference in this experiment can not only be caused by genetic differences, but it can also be due to the difference in callus humidity and the effect of gamma rays.

Floods are one of the most abundant and destructive natural disasters that every year are caused heavy losses of life and property. Due to human activity in river systems and construction in rivers, flood damage has an upward trend. At the same time, a flood is a very complex phenomenon that connects the natural environment, people, and the social systems of their organization. Kivi Chay River is one of the flood rivers in Ardabil province, which requires comprehensive studies on flood hazards and morphological changes channel. In this research, the morphology and flood risk along the Kivi Chay River located in the south of Ardabil province are evaluated. In this regard, geomorphic quantitative indices and HEC-RAS model are used.

The most important data of the present study include topographic map scale of 1: 2000 (Ardabil Regional Water Authority), Topographic map scale of 1: 50,000, geological maps scale of 1: 100,000, digital elevation model (DEM) 12.5 meter from ALOS – PALSAR satellite, Aster Satellite images 2002 (Spatial resolution of 15 meter) Sentinel Satellite images 2020 (Spatial resolution of 10 meter) and Google Earth. In this study, GIS & RS software includes Google Earth, ENVI and Arc GIS software with HEC-GeoRAS and Planform Statistics extensions was used. Also, hydrometric stations data from Istiso, Firoozabad and synoptic stations data of Khalkhal, Firoozabad were used. In order to evaluate the planform and lateral channel changes of Kivi Chay River channel, indices of curvature coefficient, central angle and transect method were used. The transect method was also used to evaluate the lateral change of the river channel. The HEC-RAS model could calculate the water surface profile in stable flow gradual variable in rivers and artificial channels in the subcritical, supercritical and complex regimes. The calculation of water surface profile carried out from one cross section to other cross, step by step, solving energy equation in standard way(HEC, 2010).

Evaluation of Kivi Chay River channel planform using morphometric indicesIn this study Kivi Chay River was divided into four reaches. In order to evaluate the planform and lateral channel changes of Kivi Chay River channel, indices of curvature coefficient, central angle were used. The average central angle for the Kivi Chay River channel was calculated to be 103.5 degrees for 2002 and 105.5 degrees for 2020. The length of the river was calculated to be 77.12 km for 2002 and 78.43 km for 2020.The average curvature index was calculated to be 1.28 for 2002 and 1.31 for 2020. -Evaluation of lateral channel changes of Kivi Chay River using transect methodThe average value of transect index in reach (1) is about 0.579 hectares. The area of Land degradation within this reach during the period 2002 to 2020 is about 6.95 hectares. In reach (2), the average change is about 0.406 hectares. Interval (3) is the most dynamic reach of Kivi Chay River in terms of lateral changes. In reach (4) the least amount of lateral changes occurred. The average lateral change of the channel along this reach is about 0.24 hectares.-Evaluation of flood risk in Kivi Chay RiverThe results show that floods with a return period of less than 10 years do not a serious risk to human communities living in the Kivi Chay River banks. These floods mainly affect the agricultural lands along the river banks. The results also show that the parts of Khalkhal City center could be affected by floods with a return period of 25 years.

The results of morphological indices show that the planform of Kivi Chay River channel is developed meanders type. However, based on geological, geomorphological and anthropogenic characteristics, there is a lot of spatial variability in the river palanform. The palnform of the river in the first reache is mainly in the control of human factors. In this reache, the lateral change average was about 0.406 hectares. The river planform in the second reache is also of developed meanders type. Over the past 18 years, the values of the curvature coefficient and the central angle have increased in this reache. In this reache, the lateral change average during the years 2002 to 2020 was about 0.406 hectares. In the Third reache, The width of floodplain is significantly increased. In this reache, the lateral change average was about 1.319 hectares. Lateral change in the fourth reache, due to the limited width of the valley and bankful materials resistance, it has the least lateral mobility. In this research, ArcGIS software was used for spatial modeling of the Kivi Chay River from the HEC-GeoRAS extension. Simulation of Kivi Chay River flood using HEC-RAS hydrodynamic model shows very high spatial variability of flood risk along this river.

The present study investigates the effect of different insert inside the tubular heat exchanger on important thermal parameters and overall efficiency. In this regard, methods such as Design of Experiments (DOE) software and response surface methodology (RSM) Central composite design (CCD) were used to design experiments. Numerical methods and neural network modeling were also used to further strengthen the analysis and then the mentioned simulation methods were compared. In all cases, the results of this study indicate an increase in heat transfer coefficient and, consequently, an improvement in the Nusselt number due to the use of novel inserts. So that unlike the previous inserts of these inserts, in addition to rotating the current, it also has the ability to rotate. Finally, the average percentage of absolute error (MAPE) in the experimental design software modeling method and neural network is 10.77 and 0.94%, respectively, which indicates the high accuracy of the neural network method to determine the friction coefficient parameter.

In the present article, the design and construction of a 3D photocopier is discussed. This device has two main units: 3D scanner unit and 3D printer unit. Today, the need to use 3D scanners in various applications such as quality control, reverse engineering, and computer aided design and production is growing. This machine will be able to take 3D scanning and after processing the scanned image, sends a 3D model to the 3D printer unit for printing and makes a copy model of that part. One of the salient advantages of this design is its use in reverse engineering. It can make a copy model with the desired fit of a workpiece without the need for a measurement process to determine the dimensions, followed by the design process, which in many cases due to the apparent complexity of the workpiece is long, difficult and time consuming, in the least make time. It is possible to repair or change the part after taking the scan, and then send it to the 3D printer unit. Scanning the piece uses the photogrammetric method. 3D printers work with different mechanisms and technologies, the printer movement mechanism is inspired by the delta robot mechanism and printing technology, and extrusion (melting) of raw materials has been selected. The rules and principles of designing and building a 3D printer are explained. It is stated how the observance of these principles and rules will be effective in increasing the accuracy and quality of manufactured parts.

The presence of dyes in the aquatic environment can cause soil/water pollution, problems for human health, and abnormal plant growth behavior. In the present study, functionalized polyethersulfone nanofiltration membranes were prepared by ferroxane fumarate nanoparticles. Ferroxane fumarate nanoparticles were charecterized by SEM and FTIR analyzes. The effect of nanoparticles on the performance and properties of membranes was determined in terms of membrane pore size, porosity, hydrophilicity, and separation of milk powder solution by membranes. The hydrophilicity of the membranes was determined by studying the pure water flux and the contact angle of the water. Hydrophilicity increased significantly in membranes containing 0.5% wt. of ferrooxane fumarate nanoparticles. The results of measuring the pure water flux passing through the prepared membranes showed that after functionalization of the polysulfone nanofiltration membrane by ferroxane fumarate nanoparticles, the permeability of this membrane increased more than three times. The maximum flux recovery ratio and the minimum irreversible permeability decay rate obtained by M0.5 membrane were 95.20 and 4.8%, respectively.  Moreover, M0.5 showed the highest rejection for dyes of direct red 16 (99%) and methylene blue (98%). The related results proved that an antifouling fumarate ferroxane functionalized membrane can be efficiently applied for the removal of dyes.

Saffron is a triploid and sterile plant having no or little genetic variation. Mutation induction is a way of increasing genetic diversity in vegetatively propagated plants. The first step in the mutation induction is to perform a radio-sensitivity test for determining the proper dose of gamma ray. Therefore, the aim of this study was to test the sensitivity of different doses of gamma ray in two conditions of cold and non-cold treatment of saffron corms. For this purpose, a factorial experiment with two factors including cold pre-treatment (cold and non-cold) and different doses of gamma ray (0, 5, 10, 15, 20 and 25 Gy) was conducted in a randomized complete block design with three replications. Growth and morphological characteristics such as plant height, number of leaves per plant, leaf dry weight, sprouting rate and percentage in the first year (MV1), and attributes related to daughter corms and flower yield, such as mean height of the stigma and dry weight of the stigma in the second year (MV2) were measured. The results of the study showed that the effect of cold treatment, radiation and their interaction was statistically significant, with the increase in gamma dose, most of the traits decreased significantly compared to the control. The radio-sensitivity test for the mean of plant height and sprouting rate and percentage, corm weight in two levels of pre-cold treatments showed that 50% survival was in the range of 15±2 Gray. According to the radio-sensitivity test, the number of leaves per plant was less susceptible to gamma rays. In order to study the genetic diversity of the gamma-irradiated saffron. The mutated samples of saffron were evaluated using RAPD and ISSR molecular markers. Cluster analysis was performed using the UPGMA method for both marker systems. The results showed that there was polymorphism between the control samples and radiated samples. In general, the results showed that the RAPD and ISSR markers could detect the polymorphic mutants and identify saffron mutants.

In this study, in order to increase the heat transfer rate in the heaters of the City Gas Station(CGS), a classic type of a tube insert was placed into its heating coils. The use of the inserts will lead to increase in the pressure drop that maybe treated as disadvantage of using inserts in some heat exchangers. However, in this case pressure drop is quite favor phenomenon as pressure should be reduced in city gas transfer line. The type of the given insert is spiral, and is made of seamless steel in accordance with the gas pipe production standard. The inserts are embedded in eight coil paths in the heater of Mavian pressure reducing station of in Kamyaran city of Kurdistan Province with capacity of 2500 m3/h. Heat transfer enhancement up to 47% obtained, which is quite important from energy saving and environmental pollution control point of view.

Fluvial geomorphology is the study of the interactions between river channel forms and processes at a range of space and time scales (Charlton, 2008). The last two decades or so have seen a major focus in fluvial geomorphology on developing topographic monitoring and modelling techniques to better quantify channel and floodplain morphology and morphological change in three dimensions (Rumsby, 2007). Morphological change in river channels primarily consists of adjustments to channel width, depth, local channel slope, and planform (Labbe, 2011). Several studies have documented the complexity and variation in the causes and rates of lateral movement in alluvial rivers. Depending on the input conditions and planform geometry, lateral movement can take different forms including meander migration Hooke l980; Bradley and Smith 1984; Nanson and Hickin 1986; Thorne 1991; Lawler 1993; Richardson 2002, width changes Surian 1999; Winterbottom 2000; Buhman et al. 2002; Chitale 2003, and wandering, avulsion, and cutoffs in the case of braided rivers Coleman 1969; Klaassen and Masselink 1992; Warburton et al. 1993; Xu 1996; Cao et al. 2002. During the past tens or hundreds of years, in many fluvial systems, river dynamics have been significantly affected by human disturbances such as land use changes, urbanization, channelization, dams, diversions, gravel and sand mining (Surian, 2002). In this study, lateral changes of the Gara-Sou river channel have been investigated in during the last 12 years.

The most important data of the present study include topographic map scale of 1: 2000 (Ardabil Regional Water Authority), Topographic map scale of 1: 50,000 and 1: 25,000, geological maps scale of 1: 100,000, Satellite images of Sentinel (2017), IRS (2005, 2017) and Google Earth. In this study, GIS & RS software includes Google Earth, ENVI and Arc GIS software with HEC-GeoRAS and Planform Statistics extensions was used. In this research, field studies are basis for geomorphological analysis. The methodology and models used in this study can be summarized in processed satellite images to study changes river channel, the extraction of vegetation and land use; Geomorphometric indices for quantitative analysis of planform and lateral changes in the river channel.

To measure the dynamics of the Gara-Sou river channel using quantitative Geomorphometric indicators of GIS techniques were used. Therefore 271 cross sections was drawn on 31 km from the Gara-Sou river channel. The four indices of lateral movement begin with a gross measurement of total bankline change, then break down the lateral movement into width change and migration. The indices are as follows: 1: Total bankline change, E (m/year) 2: Normalized lateral movement, N (% width/year) 3: Width change, dW (m/year) 4: True migration, M (m/year). Lateral stability is measured by quantifying how much the active channel area changes with time and how much of the active channel area remains in the same place. Total movement of the channel banks (E), incorporates width change and lateral migration of the channel. The index value (E) for the first reach, 0.86, second reach, 1 and for the three reach, 0.89 was calculated. The high value of the index (E) indicates the narrowing of the channel. The normalized lateral movement rates (N) were computed by dividing the average of the right and left bank change by the active channel width averaged over the time period. This value was then divided by the number of years in the time period to get an annual rate. This Index for the first reach, 0.048%, second period, 0.2% and for the three reach, 0.057%, was calculated. Narrowing of Gara-Sou River channel, which is primarily due to reduced lateral dynamics channel. This leads to the deposition processes of erosion processes have been overcome. Occupation and establish natural vegetation on the active point bar and encroaching agricultural land to near river land and river flood plains from other important factors are narrowing of Gara-Sou river. Also the morphology of Gara-Sou River are controlled by anthropogenic variables.

In this study, lateral dynamics of Gara-Sou river channel in the recent 12 years were investigated. For this purpose, a collection of Geomorphometric quantitative variables was combined with field results. High mobility in Total Bank Line Change (E) Normalized Lateral Movement Rates (N) Gara-Sou River channel is not related to the True migration but has a strong correlation with the changes in the width of channel. The true migration rate for Gara-Sou River during the last 12 years in the study area was about 0.36 meters per year. This study tries to quantify the changes through new approaches for studies fluvial Geomorphology.

Landforms represent influential processes affecting features on the earth’s surface both in the past and in the present while providing important information about the characteristics and potentials of the earth. The shape of the terrain and features such as landforms affect the flow in water bodies, sediment transport, soil production, and climate at a local and regional scale. Identification and classification of landforms are among the most important purposes of geomorphological maps and also a fundamental step in the process of producing such maps. Geomorphologists have always been interested in achieving a proper and accurate classification of landforms in which their morphometric properties and construction processes are clearly indicated. The present study has attempted to develop a new method and identify the relationship between morphometry of landforms and surface processes using a multi-scale and object-based analysis. Extraction and classification of landforms are especially important in mountainous areas, which are considered to be dynamic due to their special physical and climatic conditions. These areas are often remote and sometimes unknown. Mountainous topography has also made them difficult to access. However, they are of great importance due to their impact on the macro-regional system. Because of this significant importance, Maku County was selected as the study area.

Maku County is located in northwestern Iran (West Azerbaijan Province) which borders Qarasu River and Turkey in the north, Aras River and the Republic of Azerbaijan in the east, Turkey in the west, and Shut County in the south. This County is located between 44° 17' and 44° 52' east longitude and 39° 8' and 39° 46' north latitude. The present study takes advantage of satellite images (sentinel-2A) with a spatial resolution of 10 m, derivatives of DEM layer (slope, maximum curvature, and minimum curvature, profile and plan curvature) and object-based methods to identify and extract landforms of the study area precisely. 

The present study applies various functions and capabilities of OBIA techniques to extract landforms precisely. These functions include texture features (GLCM), average bands in the image, geometric information (shape, compression, density, and asymmetry), brightness index, terrain roughness index (TRI), maximum and minimum curvature, texture, and etc. The image segmentation scale was first optimized in the present study using ESP tools and objects of the image were created on three levels (9, 17, and 27 scales). In the next step, sample landforms were introduced, membership weights were calculated and defined for the classes in accordance with the fuzzy functions, and finally, 14 types of landforms were extracted using object-oriented analysis.

Fuzzy method includes boundary conditions, defines membership function, and constantly considers landform changes in class definition. Thus, it seems to be ideal for the purpose of the present study. The present study used two types of data (data derived from satellite imagery and DEM layer) along with OBIA approach to extract landforms. Classification of landforms based on fuzzy theory makes it possible to collect more comprehensive information from the earth's surface. Results indicate that fuzzy object-based method has classified landforms with an accuracy of 87% and a kappa index of 85%. Considering the resolution of the images applied in the present study, all features were extracted with an acceptable accuracy except for debris. This can be attributed to the fact that debris is usually accumulated in a small area on steep mountainsides, and thus remains hidden from satellites in nadir images. OBIA approach shows a high efficiency because it can combine spectral characteristics of various types of data (i.e. images and DEM data) and their derivatives while analyzing the shape of the segment, and size, texture and spatial distribution of segments based on their class and other neighboring segments.

While research is abundant on academics’ research engagement in higher education, very little has been done to study the setbacks for research practices in English language teaching (ELT) in higher education. Adopting a qualitative research design, the present study explored the research setbacks for ELT in higher education. To this end, 10 masters students, 10 doctoral students, and 10 university instructors of ELT in different state universities in Iran took part in the study. A narrative frame was applied to collect initial data, followed by conducting individual semi-structured interviews to gain more in-depth knowledge about the participants’ research practices. Thematic analysis, used to analyse the data, uncovered a number of themes and categories addressing the masters and doctoral students’ and university instructors’ research setbacks in higher education. A number of themes were generated for the following categories of research setbacks: issues with research projects, insignificant contribution, and pressures from the immediate context. The findings are discussed in the light of the literature and the status of research practice in higher education, and implications are suggested for research practice in higher education.

Floods are one of the most abundant and destructive natural disasters that every year are caused heavy losses of life and property. Due to human activity in river systems and construction in rivers, flood damage has an upward trend. One of the most important actions to reduce flood damage is the provision of flood hazard zoning maps and their use in spatial planning. In this study, the risk of flood in the Nirchay River Basin that located Ardebil province was investigated. For this purpose, the HEC-HMS model was used to simulate rainfall-runoff and to identify flood zones and fuzzy logic in order to overlay the layers and prepare a flood hazard zoning map.The simulation results show the high performance of the HEC-HMS model in simulating rainfall-runoff of the Nirchay River Basin and estimating peak flood discharges. Rainfall conversion to runoff at the Nirchay River Basin controlled by slope and land-use.The most runoff height and peak flow in Nirchay River Basin are located in the upstream sub-basins. This is due to the steep, low permeability soil, frequency impervious surfaces and high CN. The combination of layers using fuzzy logic has shown that about 8.6% of the surface of the basin are located with a high risk of flooding. These zones are located mainly on the floodplain of the Nirchay Basin. Due to the Low valley width and low slope, these lands are always at flood risk. Most settlements in the study area are located at downstream of the basin. This has increased the risk of flooding.

Sufficient genetic variation is an essential source for having a successful breeding program. Mutation is known to be a high throughput technique to induce genetic variation in plants. Irradiation is the most common method of inducing mutations in plants mutation breeding programs leading to the production of mutants with superior genotypes. Faba bean is a crop whose diversity needs to be improved for breeding programs in Iran. Unfortunately, few researches have been carried out on mutagenesis of faba bean.

In the present study, the dose response and effects of gamma irradiation have been investigated by exposing the seeds of Vicia fabacv. Saraziri to doses of 25, 35, 45, 55, 100, and 120 Gray (Gy) in the Lab at the college of Agriculture, Shahid Chamran University of Ahvaz in 2013 to 2015. The implementation of the research was under the guidance and in cooperation with the Atomic Energy Organization of Iran. The experiments were assigned as a completed block design with four replications in both laboratory and the field.

The results of the analysis of the variance indicated that there was no significant difference in germination trait of M0 generation in the seeds at various gamma irradiation doses whereas, germination rate, seedling length, and weight were significantly altered at varied doses (P≤0.05), and further responses of these traits decreased as the dosage increased. Moreover, increasing the irradiation doses caused a delay in flowering, pod setting, and pod ripening period in M2 generation. A linear regression between different characters and gamma doses was detected. Lethal dose, 50% (LD50) for fertility and seed setting, was detected as between 60-65 Gy based on reproductive traits. The principal component analysis revealed information that the first two components within the traits at the different doses were accounted for approximately 71% of the total variance. Using the biplot diagram of the first two components, 320 mutant plants appeared and the superior one within plants was identified as compared to control.

This research is reported the optimum dose of gamma irradiation of 50 to 55 Gy to exert mutation induction in Vicia Faba based on the LD50 of vegetative and reproductive phases. The findings of the current work acquired several promising mutants that might be used as beneficial sources to develop new faba bean cultivars.

The changes in river processes due to river discharge and sedimentation as a primary principle driving force can affect the geometry of rivers. Determining the amount of sediment and floodplain and water quality study are prerequisites for river management operations. Any change in the steady-state of the rivers will result in physical changes in the rivers and a new reaction to the rivers' behavior. Morphological studies to determine the quantity and quality of river response will predict future river behavior. The downstream river reaches of the Hamzekhanloo River basin is one of the most important agricultural areas of Germi city due to its fertile flood plains and sufficient water availability, which has undergone many changes in recent years. In this study, the Hamzekhanloo River was investigated based on the Rosgen stream classification scheme.

The Hec-Ras hydrodynamic model was used to simulate the Hamzekhanloo River cross-sections and floodwater capacity. The processing of the required data for modeling purposes was performed at the ArcGIS software; the classification of stream reaches was done using the Rosgen stream classification system. Rosgen classification system predicts river behavior based on morphology and hydraulic relationship and flow sediment with specific morphology. Based on Rosgen's method, morphological characteristics of rivers are investigated at four different levels but focuses more on two levels of general geomorphic properties and morphological description. Level 1 (General Classification): Describes the morphological characteristics of the river obtained by combining information on catchment, landform, and valley morphology. Level two (descriptive classification) of the river.

The results of the Rosgen classification scheme showed that the studied river had been classified at the C class in some river reaches, which had high flood sensitivity, high vegetation control, high sediment recovery, and sediment supply potential. Also, these reaches had narrow to wide valleys, constructed from alluvial deposition with a well-developed floodplain. Meanwhile, some sections of the study river fall in the B class according to the Rosgen classification. These reaches exist primarily on moderately steep to gently sloped terrain, resulting in narrow valleys that limit the development of a wide floodplain. These streams display a low channel sinuosity, and streambank erosion rates are normally low. The sensitivity to flooding and sediment supply is high; the influence of moderate vegetation control and recovering potential is excellent. Moreover, the cross-section patterns in the river and the parameters affecting the classification and segmentation of reaches are consistent with the overall pattern on the Rosgen classification model.

The river bed of the Hamzekhanloo River is a combination of rubble, gravel, and sand. Farmers and gardeners dig the riverbed and store water to irrigate the orchard fields and gardens during the summer, and crop cultivation is observed in the river bed and floodplain. Sand mining is a common activity in the river bed to carry out the development and construction purposes of the area. Sand removal from the riverbed has led to the formation of ponds within the basin, and such alterations have altered the bed and morphology of the Hamzekhanloo River. Thus, Rosgen's model can predict the geomorphic quantification of the Hamzekhanloo River and rivers with similar conditions. This type of river channel morphological classification can be used to develop engineering designs and management implications and river restoration.

In recent years, the interest in chitosan nanoparticles has increased due to their application, especially in drug delivery. The main aim of this work was to find a suitable method for simulating pharmaceutical nanoparticles with computational fluid dynamics (CFD) modeling and use it for understanding the process of nanoparticle formation in different types of microchannels.

Active and passive microchannels were compared to find the advantages and disadvantages of each system. Twenty-eight experiments were done on microchannels to quantify the effect of 4 parameters and their interactions on the size and polydispersity index (PDI) of nanoparticles. CFD was implemented by coupling reactive kinetics and the population balance method to simulate the synthesis of chitosan/tripolyphosphate nanoparticles in the microchannel.

The passive microchannel had the best performance for nanoparticle production. The most uniform microspheres and the narrowest standard deviation (124.3 nm, PDI = 0.112) were achieved using passive microchannel. Compared to the active microchannel, the size and PDI of the nanoparticles were 28.7% and 70.5% higher for active microchannels, and 55.43% and 105.3% higher for simple microchannels, respectively. Experimental results confirmed the validity of CFD modeling. The growth and nucleation rates were determined using the reaction equation of chitosan and tripolyphosphate.

CFD modeling by the proposed method can play an important role in the prediction of the size and PDI of chitosan/tripolyphosphate nanoparticles in the same condition and provide a new perspective for studying the production of nanoparticles by numerical methods.

In this study, Ni+2 removal from aqueous solution was investigated by concurrent usage of Fe3O4 nanoparticles and a high frequency ultrasound (1.7 MHz). In addition to Ni+2 removal, presence of the high frequency ultrasound led to being cooled photovoltaic (PV) module. Studied variables were pH and adsorbent dose (AD). Results indicated that the Ni+2 removal efficiency increased with an increase in the pH ranging from 2 to 9. Furthermore, the Ni+2 removal efficiency boosted by an increase in the AD. However, no significant enhancement in Ni+2 removal efficiency was observed at the AD above 9 g. Generally, the maximum Ni+2 removal efficiency was about 79 % for contact time of 50 min at pH=9 and AD=9 g in the presence of ultrasound. At the efficient condition (pH=9, AD=9 g and contact time=50 min), using ultrasound showed 16-20 % enhancement in Ni+2 removal efficiency compared to no ultrasound usage. From heat transfer view, it was observed that propagation of 1.7 MHz ultrasound into nanofluid significantly has cooled the photovoltaic (PV) module. Moreover, an increase in concentration of nanofluid (AD) showed a positive effect on reduction of heat from the PV module surface and maximum generated power. Obtained data demonstrated that agitating nanofluid by 1.7 MHz ultrasound decreased temperature of the PV module up to 15.5 % compared to no cooling system.