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Solar radiation incident on the earth’s surface is a fundamental input for many aspects of climatology, hydrology, biology, and architecture. In addition, it is an important parameter in solar energy applications. Due to the high cost of the measuring instruments of solar radiation, many researchers have suggested different empirical methods to estimate this essential parameter. In this study, with the help of fuzzy systems and neural networks, two models have been designed to estimate the instantaneous global solar radiation in Rafsanjan city which has a typical climatic conditions of semi-arid region of middle eastern countries. In fuzzy and neural network model, the inputs are the number of the given day in the year, time, ambient temperature and cloudiness, The comparison between the results of the models and the measurements, shows that the estimated global radiation is similar to the measurement; for fuzzy model, statistical indicators RMSE, MBE and t-test are 103.4367 \((\hbox {w/m}^{2})\), 4.1169 \((\hbox {w/m}^{2})\) and 9.1318, respectively and for ANN, they are 85.46 \((\hbox {w/m}^{2})\), 3.08 \((\hbox {w/m}^{2})\) and 5.41, respectively. As the results indicate, both models are able to estimate the amount of radiation well, while the neural network has a higher accuracy. The output of the modes for six other cities of Iran, with similar climate conditions, also proves the ability of the proposed models. 相似文献
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G. Behzad Zamani 《Central European Journal of Geosciences》2011,3(1):77-89
In this paper, the state of stress in the northern Tabas block in east-central Iran is analyzed based on the systematic inversion of aftershock focal mechanisms from the 1978.09.16 Tabas earthquake, to characterise the stress regime that controls most earthquakes in this area. Here, stress inversions of double-couple focal mechanisms of earthquakes recorded during the 30 days following the main shock have been carried out. The calculated average stress regime indicates dominant major 226° to 237° trending compression for the Tabas region. The dominating regime in east-central Iran is thrusting with a minimum stress axis, σ 3, close to vertical. The reconstruction of the main seismotectonic stress in east-central Iran with a NE-SW compression is consistent with independent information of the active plate convergence related to Arabia-Eurasia convergence. Most earthquakes in the mentioned area occur near or around concealed Quaternary thrust faults with their activity being controlled by the NE-SW compression. Where ?, the ratio of principal stress differences, is 0.5, a small difference between σ 2; σ 3 and σ 1 and small amounts of deviatoric stress is indicated. Therefore, for small deviatoric horizontal σ 1 it is not possible to increase and reactivate small sections of basement thrust faults and create secondary basement aftershocks. Reconstructed stress regimes in this study for sedimentary cover (237) and basement (226) of Tabas are similar. Therefore, it seems that the basement and cover were coupled together, possibly along the 2–4 km of upper Precambrian low-grade metamorphic rocks. Then these segments of the fold-and-thrust belt were involved in similar seismic activity under a similar stress regime. 相似文献
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Zamani Reza Akhond-Ali Ali-Mohammad Roozbahani Abbas Fattahi Rouhollah 《Theoretical and Applied Climatology》2017,129(3-4):1109-1121
Water shortage and climate change are the most important issues of sustainable agricultural and water resources development. Given the importance of water availability in crop production, the present study focused on risk assessment of climate change impact on agricultural water requirement in southwest of Iran, under two emission scenarios (A2 and B1) for the future period (2025–2054). A multi-model ensemble framework based on mean observed temperature-precipitation (MOTP) method and a combined probabilistic approach Long Ashton Research Station-Weather Generator (LARS-WG) and change factor (CF) have been used for downscaling to manage the uncertainty of outputs of 14 general circulation models (GCMs). The results showed an increasing temperature in all months and irregular changes of precipitation (either increasing or decreasing) in the future period. In addition, the results of the calculated annual net water requirement for all crops affected by climate change indicated an increase between 4 and 10 %. Furthermore, an increasing process is also expected regarding to the required water demand volume. The most and the least expected increase in the water demand volume is about 13 and 5 % for A2 and B1 scenarios, respectively. Considering the results and the limited water resources in the study area, it is crucial to provide water resources planning in order to reduce the negative effects of climate change. Therefore, the adaptation scenarios with the climate change related to crop pattern and water consumption should be taken into account.
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I. Rezapour T. Jasemizad M. Ayatollahi M. Zamani S. Aghaei A. Jebali 《International Journal of Environmental Science and Technology》2016,13(4):1109-1122
The aim of this study was to evaluate a computer-based method to find a new inhibitor for polyphenol oxidase (PPO) in banana, apple, and mushroom. First, the sequence of PPOs was separately obtained from Protein Data Bank, and their homology was investigated. Next, the same structure of their active site was found, and it was interacted with various phenolic and benzoic compounds by a molecular dynamic software. Moreover, the inhibition of enzymatic browning was also investigated at different laboratory conditions. This study showed that histidine–leucine–phenylalanine–histidine was in all types of PPOs. Also, molecular dynamic simulation showed that (3S)-2-(3,4-dihydroxyphenyl)-3,5,7-chromanetriol (DHPC) is the best compound to interact with PPOs. Based on experimental tests, DHPC had the highest efficacy at 4 °C. The decrease in inhibition of enzymatic browning was seen with the increase in temperature. Also, the decrease in pH led to increase in enzymatic browning. It could be concluded that DHPC is a good inhibitor for enzymatic browning. It seems that this compound can be used in different fruits and vegetables to inhibit enzymatic browning. 相似文献
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M. Taghdiri N. Zamani 《International Journal of Environmental Science and Technology》2013,10(1):19-26
The adsorption of hexamine onto powdered activated carbon from aqueous solutions was studied in a fixed bed system. Langmuir, Freundlich, Redlich–Peterson and Toth isotherm models were used to fit the experimental data and isotherm parameters were determined. The results revealed that the adsorption isotherm models fitted the data in the order of Langmuir > Toth > Redlich–Peterson > Freundlich. Lagergren pseudo-first order kinetic model was found to correlate well with the experimental data. The effects of solution pH, temperature, initial hexamine concentration and added salts concentration on the adsorption capacity and the rate of adsorption were studied. The results indicate that the rate of adsorption increases and then decreases as temperature of the hexamine solution increases, however, the adsorption capacity decreases. The addition of low concentration of salt significantly increases the adsorption capacity of activated carbon. The results showed that the activated carbon has potential for the adsorption of hexamine from industrial hexamine wastewater. 相似文献
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This study examined the spatial-temporal variations in seismicity parameters for the September 10th, 2008 Qeshm earthquake in south Iran. To this aim, artificial neural networks and Adaptive Neural Fuzzy Inference System (ANFIS) were applied. The supervised Radial Basis Function (RBF) network and ANFIS model were implemented because they have shown the efficiency in classification and prediction problems. The eight seismicity parameters were calculated to analyze spatial and temporal seismicity pattern. The data preprocessing that included normalization and Principal Component Analysis (PCA) techniques was led before the data was fed into the RBF network and ANFIS model. Although the accuracy of RBF network and ANFIS model could be evaluated rather similar, the RBF exhibited a higher performance than the ANFIS for prediction of the epicenter area and time of occurrence of the 2008 Qeshm main shock. A proper training on the basis of RBF network and ANFIS model might adopt the physical understanding between seismic data and generate more effective results than conventional prediction approaches. The results of the present study indicated that the RBF neural networks and the ANFIS models could be suitable tools for accurate prediction of epicenteral area as well as time of occurrence of forthcoming strong earthquakes in active seismogenic areas. 相似文献
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Landfill site selection using integrated fuzzy logic and analytic network process (F-ANP) 总被引：2，自引：2，他引：0
Locating a suitable place to dispose the municipal solid wastes hygienically (sanitary landfill) is one of the fundamental subjects relating the environmental stability of cities and, in general, the human settlements. This final stage of solid waste management requires observance of a series of principles and criteria mainly including environmental, social, economical, and general acceptance criteria. The set of these criteria along with their sub-criteria causes some complexities in decision making for landfill site selection. Considering effective parameters and criteria, we developed an integrated fuzzy logic and analytic network process (i.e. F-ANP) to locate a suitable location for landfilling municipal solid wastes generated in Kahak Town, Qom, Iran. Our findings revealed that integration of fuzzy logic and ANP can give better idea compared with other models like AHP, fuzzy logic, and ANP (individually). Therefore, this model can be applied in site selection for landfill of other similar places. 相似文献