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Mapping spatial distribution of climatological parameters with a good degree of accuracy is crucial in environmental modeling and planning. Nowadays, there are various models to estimate and predict spatial variables in an area but some such as cokriging and geographically weighted regression (GWR) have got more attention from experts in this field. The objectives of this study are to evaluate and compare GWR with ordinary cokriging (OCK) techniques for estimating the mean annual air temperature (MAT) of Iran using European Centre for Medium-Range Weather Forecasts (ECMWF) data and auxiliary variables (e.g., longitude, latitude and altitude). The MAT-gridded data for Iran was collected in pixels during the time interval of 1987–2015 from the ERA-Interim re-analysis version of ECMWF. Validation results indicate that cokriging model with latitude and altitude for estimating MAT has the lowest MAE (0.0155), MBE (0.00085), RMSE (0.0251), and the highest NS (0.9999) in relation to other cokriging methods. On the other hand, GWR with altitude has better results than those of GWR with other auxiliary variables because of its MAE (0.1271), MBE (0.0124), RMSE (0.1760), and NS (0.9969). By comparing two mentioned methods, cokriging with latitude and altitude has provided the best performance in relation to GWR for prediction of MAT in Iran. To obtain accurate estimation of the spatial distribution of MAT, local residuals were analyzed. Results concluded that residuals of the OCK model have high spatial adaptations between the observed and predicted MAT data compared to the GWR model. Hence, OCK was a relatively optimum method for the estimation of MAT compared with GWR.

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Titanium dioxide (TiO2) nanoparticles were prepared by sol gel route. The preparation parameters were optimized in the removal of 4-nitrophenol (4-NP). All catalysts were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). An artificial neural network model (ANN) was developed to predict the photocatalytic removal of 4-NP in the presence of TiO2 nanoparticles prepared under desired conditions. The comparison between the predicted results by designed ANN model and the experimental data proved that modeling of the removal process of 4-NP using artificial neural network was a precise method to predict the extent of 4-NP removal under different conditions.  相似文献   
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Introduction. The majority of industrial accidents occur because of human errors. Human error has different causes, however, in all cases cognitive abilities and limitations of human play an important role. Occupational cognitive failures are cognitively-based human errors that occur at work. The aim of this study was to examine the relationship between occupational cognitive failures and safety consequences. Method. Personnel of a large industrial company in Iran filled out an occupational cognitive failure questionnaire (OCFQ) and answered questions on accidents. Univariate and multiple logistic regression analysis were used to determine the relationship between cognitive failures and safety consequences. Results. According to developed regression models, personnel with a high rate of cognitive failure, in comparison to low rate, have a high risk of minor injury involvement (OR 5.1, 95% CI [2.62, 10.3]); similar results were for major injury and near miss. Discussion. The results of this study revealed usefulness of the OCFQ as a tool of predicting safety-related consequences and planning preventive actions.  相似文献   
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The synthesis of silver doped nano-particulate titanium dioxide (Ag/TiO2) using a microemulsion method and an investigation of its photocatalytic activity for the degradation of Acid Red 27 in distilled water under UV-irradiation is reported. The prepared Ag/TiO2 is characterized using transmission electron microscopy, X-ray diffraction, and energy-dispersive X-ray spectroscopy. The size of the Ag nanoparticles is around 5–15?nm, with almost uniform distribution on the TiO2 particles. The efficiency of the photocatalytic process is evaluated to establish the optimum conditions, found to be at 2?wt% of Ag loading on TiO2, catalyst dosage of 400?mg?L?1, and calcination temperature of 300°C. Complete decolorization of the dye solution on Ag/TiO2 was observed in 20?min of UV irradiation in the optimum conditions.  相似文献   
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Planning for the future is uncertain, and scenario analysis is a method of coping with the uncertainties of future plans. This paper addresses how to deal with future uncertainties by using scenario analysis as a possible approach for conducting a strategic environmental assessment (SEA). Although scenario-based approaches have been linked to strategic planning and SEA, this paper for the first time proposes how a combined approach may be implemented using specific tools and methodologies and, further on, it also implements the first three stages of the six stages proposed for the ‘scenario-based strategic planning’ approach. This work is an attempt to standardize SEA and scenario analysis as a combined approach. The three stages are tested within the Tourism Development Plan of the Iranian province of Gilan, which has been selected as a case study.  相似文献   
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A new kinetic method has been developed for the determination of iodine in water samples. The method is based on the catalytic effect of I? with the oxidation of Indigo Carmine (IC) by KBrO3 in the sulfuric acid medium. The optimum conditions obtained are 0.16 M sulfuric acid, 1?×?10?3 M of IC, 1?×?10?2 M KBrO3, reaction temperature of 35°C, and reaction time of 80 s at 612 nm. Under the optimized conditions, the method allowed the quantification of I? in a range of 12–375 ng/mL with a detection limit of 0.46 ng/mL. The method was applied to the determination of iodine in river and city water samples with the satisfactorily results.  相似文献   
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Objectives. The aim of this study was to assess the relationship between occupational cognitive failures (OCFs) and unsafe behaviors, accidents and driving offences among municipal bus drivers in Tehran, Iran. Methods. Systematic random sampling was used to select 190 drivers from 3 transport and traffic Tehran districts. Data were collected with the occupational cognitive failure questionnaire (OCFQ), the driver behavior questionnaire and a data collection form. Results. The mean (SD) numbers of driving-related offences and road traffic accidents were 1.5 (2.6) and 0.37 (1.0), respectively. The mean (SD) numbers of deliberate driving violations, unintended violations, driving slips and mistakes were 6.97 (5.5), 1.61 (1.5), 13.6 (9.0) and 4.53 (3.28), respectively. The mean (SD) number of the OCFs was 28.9 (20.5). A significant correlation was found between occupational cognitive error and unsafe driving behavior subscales. The stepwise logistic regression results showed that, while controlling the effects of confounding factors, the OCF predicts 6%, 9%, 15% and 9% of deliberate violations, unintended violations, driving slips and driving mistakes, respectively. Conclusion. The results of this study show that the score of the OCFQ is a predictor of unsafe driving behaviors and its subscales.  相似文献   
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The current work deals with ZnO-Ag nanocomposites (in the wide range of x in the Zn1 − xO-Agx chemical composition) synthesized using microwave assisted solution combustion method. The structural, morphological and optical properties of the samples were characterized by XRD (X-ray diffraction), FTIR (Fourier transform infrared spectrometry), SEM (scanning electron microscopy technique), EDX (energy dispersive X-ray spectrum), ICP (inductively coupled plasma technique), TEM (transmission electron microscopy), BET (Brunauer–Emmett–Teller method), UV–Vis (ultraviolet–visible spectrophotometer) and photoluminescence spectrophotometer. The photocatalytic activity of the ZnO-Ag was investigated by photo-degradation of Acid Blue 113 (AB 113) under UV illumination in a semi-batch reactor. This experiment showed that ZnO-Ag has much more excellent photocatalytic properties than ZnO synthesized by the same method. The enhanced photocatalytic activity was due to the decrease in recombination of photogenerated electron-holes. The results showed the improvement of ZnO photocatalytic activity and there is an optimum amount of Ag (3.5 mol%) that needs to be doped with ZnO. The effect of operating parameters such as pH, catalyst dose and dye concentration were investigated. The reaction byproducts were identified by LC/MS (liquid chromatography/mass spectrometry) analysis and a pathway was proposed as well. Kinetic studies indicated that the decolorization process follows the first order kinetics. Also, the degradation percentage of AB 113 was determined using a total organic carbon (TOC) analyzer. Additionally, cost analysis of the process, the mechanism and the role of Ag were discussed.  相似文献   
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Objective. Construction is a hazardous occupation due to the unique nature of activities involved and the repetitiveness of several field behaviors. The aim of this methodological and theoretical review is to explore the empirical factors influencing unsafe behaviors and accidents on construction sites. Methods. In this work, results and findings from 56 related previous studies were investigated. These studies were categorized based on their design, type, methods of data collection, analytical methods, variables, and key findings. A qualitative content analysis procedure was used to extract variables, themes, and factors. In addition, all studies were reviewed to determine the quality rating and to evaluate the strength of provided evidence. Results. The content analysis identified 8 main categories: (a) society, (b) organization, (c) project management, (d) supervision, (e) contractor, (f) site condition, (g) work group, and (h) individual characteristics. The review highlighted the importance of more distal factors, e.g., society and organization, and project management, that may contribute to reducing the likelihood of unsafe behaviors and accidents through the promotion of site condition and individual features (as proximal factors). Conclusion. Further research is necessary to provide a better understanding of the links between unsafe behavior theories and empirical findings, challenge theoretical assumptions, develop new applied theories, and make stronger recommendations.  相似文献   
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