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Before teachers can transform the reality and promote a liberating education within mainstream educational contexts, they must first gain a thorough understanding of how learners perceive the world. In an attempt to gauge EFL learners’ perceptions, the present study set out to conceptualize the construct of Critical Digital Pedagogy (CDP) by developing and validating a questionnaire for use in online EFL settings. The researchers distributed a preliminary questionnaire with 65 items to 380 adult Iranian EFL learners and used Exploratory Factor Analysis as well as Confirmatory Factor Analysis (EFA, CFA) to analyze the results. After removing 9 items, the final questionnaire consisted of 56 items on a five-point Likert scale. The analysis revealed that CDP consists of 10 factors, namely “consciousness raising,” “community and collaboration,” “empowerment and agency,” “inclusivity,” “dialogism,” “co-creation of materials,” “praxis,” “problem-posing education,” “teachers as transformative intellectuals,” and “critical thinking and reflection.” Additionally, the convergent validity as well as the reliability of the questionnaire to measure the intended construct was statistically confirmed. These findings have important implications for EFL teachers, curriculum developers, course designers, and language researchers as they increase awareness of CDP and its underlying components.

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In this research, an intelligent method is introduced for remaining useful life prediction of an internal combustion engine timing belt based on its vibrational signals. For this goal, an accelerated durability test for timing belt was designed and performed based on high temperature and high pre tension. Then, the durability test was began and vibration signals of timing belt were captures using a vibrational displacement meter laser device. Three feature functions, namely, Energy, Standard deviation and kurtosis were extracted from vibration signals of timing belt in healthy and faulty conditions and timing belt failure threshold was determined. The Artificial Neural Network (ANN) was used for prediction and monitoring vibrational behavior of timing belt. Finally, the ANN method based on Energy, Standard deviation and kurtosis features of vibration signals was predicted timing belt remaining useful life with accuracy of 98%, 98% and 97%, respectively. The correlation factor (R2) of vibration time series prediction by ANN and based on Energy, Standard deviation and kurtosis features of vibration signals were determined as 0.87, 0.91 and 87, respectively. Also, Root Mean Square Error (RMSE) of ANN based on Energy, Standard deviation and kurtosis features of vibration signals were calculated as 3.6%, 5.4% and 5.6%, respectively.

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In this study, the relative humidity of the gases in the PEM fuel cell was changed and its effect on electro-osmotic flow was investigated. ‎By changing the humidity on both sides of the fuel cell and using the water balance equations, the values of the electro-osmotic flow, ‎electro-osmotic coefficient and net drag in different humidity levels were found. Results showed that variations of the electro-osmotic ‎flow changed linearly by anode and cathode humidity to the special humidity and after that not much variation was seen. In addition, the ‎results revealed that humidity change at anode had more desirable effect than the cathode. For example, at 70% anode humidity and 35% ‎cathode humidity with the current of 5A, the value of electro-osmotic flow was obtained as 2.66639E-06 mol/cm2.s, while in the former ‎‎35% and the latter 70% with the same current, this value was recorded as 2.56418E-06 mol/cm2.s. In addition, results showed that the‎‏ ‏variations of the electro-osmotic coefficient changed linearly by humidity. It was determined the current change of fuel cell has not so ‎effect on the curves of electro-osmotic coefficient. The electro-osmotic coefficients varied between 0.636001 and 1.632476, which were ‎in a good agreement with the values obtained in other related papers. In addition, the variations of the net drag in respect of humidity were ‎investigated, too. It was determined that the net drag changed linearly by the cathode humidity with positive slope, but its variations by ‎the anode humidity were linearly with negative slope.‎

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The significant role of institutional conditions created by government and institutions involvement in the process of achieving sustainable development has attracted attention of policy makers to institutional innovation as one of the fundamental concepts in development strategies. On the other hand, achieving sustainable development requires access to technology and making appropriate policies for technology and innovation. This study seeks to denote the relationship between institutional innovation, technology development and the achievement of sustainable development using a partial least squares (PLS) model. The proposed model applying a questionnaire distributed among science and technology experts was estimated. The results show that institutional innovations as soft technologies will play great roles in achieving sustainable development and technology development. In addition, among technology innovations, strategizing and policy-making with a coefficient of 0.92 is of greatest importance in attaining sustainable development. As well, among technology development evidences, patent and copyright, technology management and technology environment with coefficients of 0.904, 0.89 and .0898 respectively have the highest significance in achieving sustainable development.

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In this paper, a vibration-based damage detection approach for multi-layered woven glass laminate using time signal processing and Neural Network (NN) is presented. In order to reduce noise in the experimental extracted signals, wavelet-based denoising has been applied. After data mining and feature extraction from processed signals, NN as a classifier is employed to detect the damaged GFRP. Different NN structures were tested in order to enhance the damage detection performance to recognize the most remarkable performance. Also, the performance of the presented method was evaluated when different mother of wavelets at different decomposition levels denoise signals so that the best signal processing method is selected. The results demonstrate the effect of NN structure on the damage detection technique, which in this research the best NN performance was obtained with 75 hidden layers and allocating 80%, 10% and 10% of data to training, evaluation and testing, respectively. Furthermore, denoising using db3 and bior3.7 mother wavelets at 2nd decomposition level leads to the highest accuracy as well as suitable calculation time compared to other mother wavelets. The proposed method based on real data at the data acquisition points detects damage in composite laminate with high accuracy at reasonable calculation time, hence it can be used for condition monitoring of composite laminate either offline or online, provided that adding online data acquisition equipment.

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The interaction between soil and geosynthetics has great importance in engineering work, especially in design and stability analysis of geosynthetic-reinforced geotechnical structures. In recent decades, several laboratory methods have been performed to properly understand the interaction between soil and geogrids, including pullout test, large-scale direct shear test. Although factors such as the geometry of the reinforced soil system and its construction process may affect the interaction properties between the soil and the geosynthetic, these properties are strongly influenced by the physical and mechanical properties of the soil and the geometrical and mechanical properties of the geosynthetic. Pullout test determines the geosynthetic pullout resistance, which is an important design parameter in relation to the internal stability of geosynthetic-reinforced geotechnical structures, and allows the measurement of displacements throughout the specimen during the pullout testing. Pullout force refers to the tensile force required to create an external sliding of geogrid embedded in soil mass. The tensile strength of the reinforcement consists of the frictional resistance on the surface of the longitudinal and transverse members of the geogrid and the passive resistance that is mobilized against the transverse members. Although fine-grained soil is recommended in the design of geosynthetic-reinforced soil structures, many geosynthetic-reinforced soil structures are constructed using soil containing a fine percentage. Therefore it is important to investigate the effect of fine grains on the stability and performance of such soil structures under different loading conditions. Geosynthetic-reinforced soil structures are sometimes affected by cyclic loads due to traffic and train crossings, vibration of industrial machinery, wave and earthquake. In this study, by performing static and multistage pullout tests, the static and post-cyclic pullout behavior of a uniaxial geogrid manufactured in Iran under the brand GPGRID80/30 is presented. The tests were carried out on a large scale pullout box with a dimension of 90 × 50 × 50 cm and with a constant rate and multi-stage procedures on three different soil types including clean sand, sand containing 10 and 20% fine silt and three effective vertical stresses of 20, 40 and 60 kPa. Results show that geogrid static pullout resistance increases with increasing effective vertical stress in all three different soil types. Also, the increase of silt in the sandy soil resulted in an increase in the monotonic maximum pullout resistance at effective stress of 20 kPa. The geogrid behavior in all three soils for 20 kPa vertical effective stress was strain softening and for the 40 and 60 kPa vertical effective stress ​​the geogrid pullout behavior was strain hardening. However, 10% increase in silt content leads to a slight decrease in monotonic pullout resistance and a 20% increase resulted the slight increase in monotonic pullout resistance of geogrid at vertical stress of 40 and 60 kPa. As the amount of silt content increased, the effect of cyclic loading on post-cyclic resistance increased, especially in vertical effective stresses of 40 and 60 kPa. Also, at effective stress of 20 kPa, the geogrid post-cyclic resistance decreased in all three sands, sand containing 10% silt and sand containing 20% silt relative to its corresponding monotonic pullout resistance.

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In a reinforced concrete member, especially in a beam, mechanisms of shear transfer are as follows:1. The force created in shear bars after diagonal cracks, 2. The shear capacity of the concrete in a part of the compressive region of the concrete with no crack, 3. The forces from the aggregates interlock at both sides of the crack, 4. The force due to the dowel action of the flexural bars that connect both sides of the crack and create resistance against shear deformation of the crack. Dowel action can be defined as follows: the ability of the longitudinal bars to transfer the force perpendicular to their axis. The distance between the longitudinal axis of the non-deformed parts at both sides of the crack is considered as the deformation of the dowel bar.
To be able to analyze and design the reinforced concrete structure members correctly, their behavior must be evaluated under different loadings. The efficiency, accuracy, and speed of the structure analysis techniques depend on using suitable behavior models. In reinforced concrete structures, the concrete will be cracked under normal loadings due to its weakness in tension. Therefore, it is important to know the mechanisms of stress transfer in the cracked surfaces to evaluate the response of the reinforced concrete structures. In recent years, an extensive experimental and analytical study on the effect of longitudinal bars in shear transferring (dowel action) has done. Almost all the models presented the theory of Beam on Elastic Foundation (BEF) as the best way to simulate the behavior of the dowel action. In this model, the subgrade stiffness of concrete is the most important parameter. BEF model is a linear model because the dowel bar and its surrounding concrete are modeled by a uniaxial element on a row of springs. The advantage of the linear models is that they gather all features of the concrete and the interaction of the concrete-bar in a bearing stiffness coefficient. For this reason, a suitable formulation is required for it to model the beam behavior from the elastic stage to the failure. In the elastic state, the bearing stiffness can be presented as a constant like BEF traditional models. However, in the nonlinear state, the stiffness must be a function of displacement to model the failure due to the load.
 In the present research, an experimental program is followed on the beam-type specimens to identify the behavior of the cracked surfaces under the effect of the shear. Using the test specimens made of ultra-high performance concrete, the shear transferred through a longitudinal bar (dowel action) is measured. The shear response of the dowel bar, the subgrade stiffness, and the displacements are measured. Furthermore, suitable formulations are proposed for the UHPC subgrade stiffness.  Based on the results of the tests and using the studies of other researchers, a suitable model is presented for the shear mechanism through the bar in the cracked surfaces of ultra-high performance concrete. The results show the suitable precision of the proposed relations to estimate the dowel displacement-shear curve in the specimens with vertical and inclined cracks.