Showing 13 results for nikbakht
Volume 0, Issue 0 (Articles accepted at the time of publication 2024)
Abstract
The present research study aimed to investigate the pragmatic awareness, attitudes, and practices of nine upper secondary English teachers in EFL (English as a Foreign Language) classrooms, with a focus on the intercultural aspects of the subject. Using a phenomenological methodology, the study conducted nine semi-structured interviews with English teachers of upper secondary students. Teachers demonstrated a high level of awareness of pragmatics, particularly when presented with pragmatic input based on syllabi formulations. The awareness suggested a recognition of the importance of pragmatic competence in language learning. Teachers incorporated pragmatics into their teaching methods. Pragmatics was used as a tool for fostering metacognitive conversations about language, helping students understand the appropriateness of certain phrases or words. Teachers aimed to make students aware of why people communicate in certain ways. The understanding of the reasons behind communication choices was deemed important for both teachers and students. Teachers perceived the intercultural dimensions of the English subject as crucial. Issues such as monocultural teaching groups, filter bubbles, and the rise of difficult conversations were highlighted. Teachers found using students' first languages to be an important tool for understanding and scaffolding their learning of English. The incorporation of pragmatics in the EFL classroom not only benefits language development but also serves as a facilitator in developing an understanding of other people. The study suggested a link between pragmatic awareness and intercultural competence in language teaching.
Volume 5, Issue 3 (summer 2020)
Abstract
Aims: Recently, there has been an increasing attention in workplace health-related issues. The issue of MusculoSkeletal Disorders (MSDs) has obtained considerable critical attention. In this regard,work station has a pivotal role in prevention of MSDs. This study was conducted to assess Work-Related Musculoskeletal Disorders (WMSDs) among a sample of Iranian computer users.
Method and Instruments: A cross-sectional study was conducted on office computer users of a university in Tehran. The sample size of 435 people were randomly selected from the university employees. A standardized questionnaire was used to collect data. The data were analyzed using Spss.
Findings: The results revealed that the pain was frequently felt in the region of neck (64.4%), shoulder (60.9%) and wrist complaints (52.4%). The current study showed a high prevalence of MSDs among computer users. In addition, according to workstation questions, it was reported that there were no support device in for supporting lower back and arm in the workstation equipments.
Conclusion: Workstation is one of the essential factors for the prevention of occupational damages in MSDs. This study recommends that there is a need to investigate office equipments as a crucial element not only for promoting performance abalities, health, safety, and efficiency improving but also in reducing complaints and pain caused by MSDs.
Volume 7, Issue 2 (No.2 (Tome 30), (Articles in Persian) 2016)
Abstract
Any discourse is the domain of producing and receiving the meaning and different factors involved in the formation of this process. Metaphor is considered as one of meaning creating elements in various types of discourses. This article has adopted a semiotic-semantic approach which takes a look at the function of discourse devices of metaphor in the production process of meaning and the way Nima Youshij communicates in discourse of his letters. By pro enunciative role we mean the use of metaphor as a technique employed by the speaker to highlight a part of the utterance, to impact further on the audience, to support the utterance, to repair the chaotic relations, to cover up emotions, to induce a certain sense to the audience in the discourse. This research is going to denote the role of metaphor in the formation of meaning and cohesion in the discourse; to evaluate the effectiveness of metaphor application and to investigate other functions of metaphor inn the discourse. Therefore, the most important communicative functions of metaphor in Nima's letters have been classified and analyzed.
Volume 11, Issue 4 (Fall 2023)
Abstract
Aims: The present study aimed to identify the predictors of hand hygiene intention and behavior among nurses using the theory of planned behavior (TPB).
Materials & Methods: This cross-sectional study was conducted on nurses working in a public hospital in Tehran in 2016-2017. In total, 196 nurses were enrolled in this study and selected through random sampling. Data were collected using a self-administered questionnaire guided by TPB. The validity of the questionnaire was measured using the opinions of 14 scholars and professors. The content validity ratio was measured based on the Lawshi method and the content validity index was measured based on Waltz and Basel method. The test-retest and internal consistency were used to determine the reliability of the questionnaire. Data analysis was performed using SPSS software 16.0 and statistical tests, including multiple regression analysis.
Findings: The attitude toward hand hygiene (p<0.001) and perceived subjective norms (p=0.012) were correlated with nurses’ intentions to hand hygiene. This set explained 56% of the variance in intention to hand hygiene. In addition, Perceived behavioral control was found as the strongest predictor of hand hygiene behavior (p<0.001), which together with subjective norms and intention could predict individuals’ behavior (R2=0.52).
Conclusion: The constructs of the TPB have predictability regarding hand hygiene behavior.
Volume 13, Issue 2 (Number 2 - 2011)
Abstract
Drying characteristics of Quercus were determined experimentally as a function of temperature, air velocity, and variety (Quercus Persica and Quercus Libani). In order to estimate and select a suitable drying curve, five different thin layer drying models were fitted to the experimental data. Experiments were performed at the air temperatures of 50, 60 and 70°C. At each temperature level, two air velocities were adjusted: 0.5 and 1m/s. The effect of air temperature was found to be significant in comparison to air velocity for drying of fresh Quercus fruits. Increasing air velocity at constant air temperature resulted in the decrease of drying time. Among all the selected drying models, the Page model was found as the best mathematical model for describing the drying kinetics of Quercus fruits. Based on the results, drying temperature of 70 oC and air velocity of 1 m/s are the optimum values for drying Quercus fruit. Drying time and Page model constants were found to be dependent significantly on the variables studied.
Volume 13, Issue 3 (Number 3 - 2011)
Abstract
The objective of this study was to investigate dehydration kinetics of barberry (Berberis vulgaris L.) at different drying temperatures (60 ºC, 70 ºC, 80 ºC), air velocities (0.3 m s-1, 0.5 m s-1, 1 m s-1) with two types of pretreatment. Drying time and colour quality during dehydration were experimentally determined. Barberries were dried from the initial moisture content of 73.44% (w.b.) to the required moisture content of 18% (w.b.). Dehydration kinetics was monitored by measuring barberries weights at regular intervals. Convective drying curves were obtained for the treated and untreated barberries. The effect of two dipping pretreatments on drying kinetics of barberries was also studied. The two pretreatments were thermal shocking by immersing barberries in hot water, followed by cold water cooling, and dipping in olive oil and food grade K2CO3. Colour of the dried product was altered significantly during drying. The results indicated that the use of low temperatures is adequate for preserving this property. The air temperature significantly affected drying time and hunter colour indices of barberries (P< 0.05). With heat shocking and treatment with olive oil and K2CO3, drying time was reduced to about 40% and 60%, respectively. The total colour change (ΔE) and hue angle (H) increased with temperature. Moisture transfer from the test samples was described by applying the Fick’s diffusion model for calculating the effective diffusivity. The effective moisture diffusivity (Deff) of barberry increased as the drying air temperature increased. The Deff values were higher for the treated samples than the untreated ones. These values were also higher for the samples treated with olive oil and K2 CO3 emulsion than those treated with hot water. The effective diffusivity of the untreated and the pre-treated varied between 2.57×10-13 and 9.67×10-12 m2 s-1, respectively. Higher colour change was observed in barberries treated with olive oil and K2CO3 emulsion. Statistical analysis showed that temperature and pretreatment had the most significant effect on drying time at p<0.01.
Volume 13, Issue 4 (Number 4 - 2011)
Abstract
Tomato is a major fruit, as well as a major food science product. There is a need of
determining the quality attributes of this fruit (nondestructively) due to the increasing
demand of the in agro-industrially controlled areas. Most of the commonly employed
techniques are time consuming and involve a considerable degree of manual work.
Sample preparation, juice making, and laboratory tests are among the limitations. Raman
spectroscopy was applied in this study to measure such important quality parameters of
tomato as SSC, pH and color. A dispersive Raman instrument was employed and
reference analyses were carried out to make calibration models regarding the spectral
features and target attributes. Analysis of the spectra revealed that all the three
characteristic bands of cartenoids, lycopene, and carotene, were significantly
recognizable. Also there were several strong to medium bands recognized as related to
carbohydrates. Principal Component Regression (PCR) and Partial Least Square (PLS)
were selected as the multivariate calibration models. The prediction models proved to be
robust resulting in a desirable mapping between the spectra and output attributes. The
Root Mean Square Error of Predictions (RMSEP) through PLS and PCR for modeling
the color index using the whole spectrum was obtained as 0.33 and 0.38, respectively.
RMSEP for mapping the SSC using PLS and PCR models was resulted in respective
figures of 0.30 and 0.38. PCA interpretation depicted that Raman spectra could make a
favorable distinction among the samples based on their maturity stages. As a result, there
is a great potential to use Raman spectroscopy in industrial approach and in line control.
Volume 14, Issue 62 (4-2017)
Abstract
Dahi is a traditional Indian fermented milk product that is similar to plain yogurt in appearance and consistency. As compared to yogurt, dahi has lower acidity, consequently it seems to be more effective in production of probiotic or synbiotic foods. The aim of this study was optimization of the production process and evaluation of physicochemical and microbial properties of synbiotic dahi by response surface methodology (RSM) based on Box Benken Design. Inulin (0-2.5%), tragacanth gum (0-0.06%) and storage time (1-19 days) were the factors that their impacts on the dependent variables were evaluated. In order to optimize variables, three traits including firmness, syneresis and viability of probiotic Lactobacillus acidophilus (LA5) were considered as responses. Finally, the appropriate power and fit of model were indicated based on determination coefficient (R2), adjusted determination coefficient and coefficient of variation (CV). The determination coefficient (R2) for firmness, syneresis and microbial counting in synbiotic dahi was obtained 0.99, 0.91, and 0.98, respectively. The increase in the concentration of inulin and storage time led to improve of syneresis and firmness of the products. Also, the increase in concentration of tragacanth up to 0.03% increased firmness, while afterward up to 0.06% concentration caused negative effect and reduced firmness. The increase in concentration of tragacanth and inulin had positive effect on probiotic counting of the products, while storage time had deleterious effect on it. According to the results of optimization experiments, optimal conditions were 2.5% concentration of inulin with 0.03% concentration of tragacanth gum in 18-day holding period.
Volume 15, Issue 1 (1-2013)
Abstract
Common drying systems, including hot air convection, infrared, vacuum and IR-convective were employed to investigate and analyze the drying process of mulberry fruits. To evaluate the effect of pretreatment on the drying phenomenon, samples were pretreated by being subjected to: microwaves, chemical preparation, mechanical as well as blanching approaches. Results revealed that the microwave pretreatment, integrated with IR-convective dryer required the lowest time needed for drying mulberries. Furthermore, the experimental data were fitted to semi empirical as well as theoretical models to achieve the most suitable function governing mulberry drying process. Eventually, Page Model proved to perform best with regard to its high coefficient of determination, low value of χ2 and root mean square of error.
Shapor nikbakht, Mohammad Eftekhari, Ghader Faraji,
Volume 17, Issue 1 (3-2017)
Abstract
There has been much interest in recent years in improving material properties by grain refinements using severe plastic deformation (SPD). With applying severe plastic deformation to metals, the structure changes and nanostructure produce. In this study, ultra-fine grained pure titanium fabricate by combination of Equal channel angular pressing and Extrusion process in different passes (1, 2, 4 and 6 pass). ECAP and Extrusion processes were carried out at 400°C. Then, mechanical and microstructural properties of UFG pure titanium billets produced b combination process of ECAP and extrusion process were examined and the effect of passes on mechanical and microstructural properties was investigated. The results showed that mechanical properties were improved significantly. Ultimate strength increased up to 941MPa, in the best state, while for initial sample was 505MPa, in other word ultimate stress increased about 86.3%. With this combinational method, ultimate stress increased about 60.8% for 1 pass sample, 78.8% for 2 pass sample, 86.3% for 4 pass sample and 80.8% for 6 pass sample rather than initial state. In higher passes the rate of increase are reduced due to the grains size saturation. Hardness increased from 81.85 Hv to 216.65 Hv; In other words, hardness increased 164% from initial value. Further passes of the process only have a minor effect on increasing of billet hardness. Scanning Electron Microscope also revealed that brittle fracture were takeplaced in all sample with shallow dimples.
Volume 17, Issue 7 (Supplementary Issue - 2015)
Abstract
Energy and mass transfer investigations in thermal processing of fruits serve as a breakthrough in the design and scale up of drying systems. Diffusivity characteristics and specific energy consumption for drying of fig fruit in a laboratory scale microwave dryer were assessed. Several intervals for microwave power intensity including 0.5, 1, 1.5, 2, and 2.5 W g-1, and 6 levels of power on-off stated as pulsing ratios of 1.5, 2, 2.5, 3, 3.5, and 4 were employed. The results showed that the drying rate decreased with the pulsing ratio and increased with microwave power intensity. Effective moisture diffusivity as an indicator of mass transfer was obtained to be higher at elevated microwave power intensities. Also, increased pulsing ratios had a reducing effect on moisture diffusivity. Using 2nd law of Fick, moisture diffusivity was calculated to be varying from 5.93E-10 to 1.42E-08 m2 s-1 depending on the experimental conditions. Furthermore, the activation energy of fig fruit was obtained to be in the range of 60.094 to 92.189 kJ mol-1. Specific energy consumption variations showed a positive correlation with pulsing ratio and drying time. However, due to the dependence of energy consumption on MW power intensity, a multiple regression analysis with R2 of 0.968 was developed.
Volume 23, Issue 5 (9-2021)
Abstract
Gerbera is one of the significant cut flower crops worldwide suffering from loss of flower quality induced mainly by Calcium (Ca) deficiency. In this research, the influence of Humic Acid (HA) and Ca in nutrient solution was studied on the growth parameters of gerbera. A completely randomized hydroponic experiment was designed by adding HA (0, 100, 500, and 1,000 mg L-1) and Ca (3.5 and 7 meq L-1 nutrient solution) to the nutrient solution of gerbera, with three replications. The effects of the treatments were evaluated on the growth, protein content, proline content, transpiration, CO2 assimilation, photosynthesis, SPAD value, number of harvested flower, and antioxidant activity in gerbera cv. Malibu. Results showed that decreasing Ca level to 3.5 meq L-1 decreased Superoxide Dismutase (SOD), Peroxidase (POD), and CO2 assimilation. However, this treatment caused an increase in Malondialdehyde (MDA), protein content, proline content, chlorophyll, and photosynthesis. Transpiration and number of harvested flowers were not affected by Ca concentration significantly. The highest level of HA (1,000 mg L-1) increased POD and transpiration (30 and 11%, respectively). However, SOD and protein content increased at 500 and 1,000 mg L-1 HA levels. When HA was accompanied with Ca, SPAD value, transpiration, and CO2 assimilation were improved, especially at high levels of HA (500 and 1,000 mg L-1) and higher level of Ca (7 meq L-1 Ca). The results suggested that HA could increase the number of harvested flowers and improve plant health by enhancing the plant enzymatic antioxidant defense system.
Sina nikbakht, Mohammad Mahdi Heyhat,
Volume 24, Issue 12 (December 2024)
Abstract
Nowadays, fresh water scarcity is one of the major concerns of the global community. To tackle the freshwater scarcity situation, several solutions have been suggested, including the extraction of water from fog-laden flow. Fog harvesting is known as a sustainable and effective approach to supplying freshwater. Various types of fog collecting elements (FCEs) have been implemented in studies to collect water from fog-laden flow. Woven meshes with square-shaped holes are among the most frequently employed FCEs in studies. One of the major drawbacks of these types of FCEs is their low water collection efficiency, particularly at low wind velocities. In this study, two alternative mesh hole geometries, triangular and hexagonal, were proposed to enhance the collection efficiency and compared with an equivalent square mesh in terms of the shading coefficient (SC). The evaluations were conducted experimentally using an experimental setup capable of mimicking atmospheric fog-laden flow at two different air velocities. The results indicate that the water harvesting rate is highly affected by mesh hole geometry. Using triangular and hexagonal meshes, compared to square mesh, can improve the water collection rate by up to 12.6% and 29%, respectively