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Majid Altafi Dadgar Parviz Zeaieanfirouzabadi Majid Dashti Rasool Porhemmat 《Arabian Journal of Geosciences》2017,10(5):114
Various groundwater potential zones for the assessment of groundwater availability in the Bojnourd basin have been investigated using remote sensing, GIS, and a probabilistic approach. Five independent groundwater factors, including topography, ground slope, stream density, geology units, lineament density, and a groundwater productivity factor, i.e., springs’ discharge, were applied. Discharge rates of 226 springs over the area were collected, and the probabilistic model was designed by the discharge rates of springs as the dependent variable. For training the probabilistic model, a ratio of 70/30% of springs’ discharge was applied and discharge rates of 151 springs were selected to randomly train the model. The frequency ratio for each factor was calculated, and the groundwater potential zones were extracted by summation of frequency ratio maps. The groundwater potential map was also classified into four classes, viz., “very good” (with a frequency ratio of >6.75), “good” (5.5FR6.75), “moderate” (4.75FR5.5), and “poor” (FR4.75). Then, the model was verified based on a success-rate curve method which resulted in obtaining an accuracy ratio of 75.77%. Finally, sensitivity analysis was applied by a factor removal method in five steps. Results reveal that topography factor has the biggest effect on the groundwater potential map and removing this factor eventuates in the lowest accuracy of the final map (AUC = 63. 73%). The groundwater potential map is fairly affected by removing the lineament density factor with an accuracy of 68.80%. Removing the lineament density factor has the lowest effect on the final map with accuracy of 68.80%. 相似文献
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Farhad Dashti Rajesh P. Dhakal Stefano Pampanin 《Bulletin of Earthquake Engineering》2018,16(1):427-458
This paper describes the blind prediction carried out to simulate the response of a thin reinforced concrete wall tested under uni-directional (in-plane) quasi-static reverse cyclic loading. The specimen was a singly reinforced T-shaped wall panel with a shear-span ratio of 3.7. The response of the test specimen was simulated prior to the release of test results using a finite element model which had already been verified for its capabilities in capturing different failure patterns of rectangular walls, particularly out-of-plane instability. The numerical model predicted a flexural dominated response for the specimen accompanied by considerable out-of-plane deformations. The blind prediction report, submitted in advance to the principal investigator of the experimental campaign, included lateral load-top displacement response of the specimen, maximum out-of-plane deformation corresponding to each drift level, evolution of out-of-plane displacements throughout in-plane loading, response of the longitudinal reinforcement at the section exhibiting the maximum out-of-plane deformation, and von Mises as well as reinforcement stress distribution at some key points of the wall response. Furthermore, a parametric study was carried out addressing the effects of shear-span ratio, reinforcement eccentricity and axial load ratio on the wall response. Results of the numerical simulation that had been included in the blind prediction report have been compared with the experimental measurements indicating that the evolution of the out-of-plane deformation was well captured by the model. 相似文献
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S. Marofi N. Parsafar G. H. Rahim F. Dashti H. Marofi 《International Journal of Environmental Science and Technology》2013,10(1):133-140
In this study, raw and treated wastewaters were reused for potato cultivation in order to verify the effect of wastewater on crop yield, crop’s heavy metals’ concentration as well as some major traits of potato. To this regard, a completely randomized test was designed with five water treatments and three replications. The watering were as follows: raw wastewater (T1), treated wastewater (T2), a combination of 50 % raw wastewater and 50 % fresh water (T3), a combination of 50 % treated wastewater and 50 % fresh water (T4), and fresh water (T5). The experiments were run during October 2009–June 2010 in the greenhouse of Bu-Ali Sina University. The results show that the effects of treatments were significant on the length and number of stems per plant (p < 0.05). The number of nodes and weight of tubers, crop yield and heavy metal (cadmium, nickel and lead) concentration in shoots and tubers were also significant (p < 0.01). The results indicated that the highest length of stem (55.44 cm) was obtained in T2 which had no significant differences from that of T1. The maximum and minimum tuber weights and crop yield were obtained in T1 and T5, respectively. Based on crop yield rate, the watering ranked as follows: T1 > T3 > T2 > T4 > T5. The maximum and minimum heavy metal values were observed in T1 and T5, respectively. Based on the cadmium, nickel and lead accumulations in shoots and tubers (except cadmium in shoots), the watering treatments ranked as: T1 > T3 > T2 > T4 > T5. 相似文献
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Poro A. Halavati A. Lashgari E. Davoudi F. Gardi A. GholizadehSoghar K. Dashti Y. Mohammadizadeh F. Hedayatjoo M. 《Astronomy Reports》2021,65(7):543-551
Astronomy Reports - We performed the first light curve analysis of GW Leo and a new ephemeris is obtained for QT Boo. The light curve investigation also yields that the system GW Leo is a contact W... 相似文献
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Using batch method, the adsorption of thallium(I) ions from aqueous solutions on eucalyptus leaves powder, as a low cost adsorbent, was studied. The effect of various modification of considered adsorbent on the adsorption percentage of Tl(I) is an important feature of this study. The results showed that the unmodified and acidic modified adsorbent are the poor adsorbents for the Tl(I) ions while basic modified adsorbent is a suitable adsorbent. Also, the effect of some experimental conditions such as solution initial pH, agitation speed, contact time, sorbent dosage, temperature, particle size, and thallium initial concentration was studied. The results showed that the adsorption percentage depends on the conditions and the process is strongly pH‐dependent. The satisfactory adsorption percentage of Tl(I) ions, 81.5%, obtained at 25 ± 1°C. The equilibrium data agreed fairly better with Langmuir isotherm than Freundlich and Temkin models. The value of qm that was obtained by extrapolation method is 80.65 mg g?1. Separation factor values, RL, showed that eucalyptus leaves powder is favorable for the sorption of Tl(I). The negative values of ΔH0 and ΔS0 showed that the Tl(I) sorption is an exothermic process and along with decrease of randomness at the solid–solution interface during sorption, respectively. 相似文献
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Latif Sarmad Dashti Ahmed Ali Najah Sathiamurthy Edlic Huang Yuk Feng El-Shafie Ahmed 《Natural Hazards》2021,109(1):351-369
Natural Hazards - Forecasting of reservoir inflow is one of the most vital concerns when it comes to managing water resources at reservoirs to mitigate natural hazards such as flooding. Machine... 相似文献
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