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261.
Rezaeian-Zadeh Mehdi Tabari Hossein Abghari Hirad 《Arabian Journal of Geosciences》2013,6(7):2529-2537
Arabian Journal of Geosciences - Prediction of monthly discharge volume is important for reservoir management and evaluation of drinking-water supplies. Also, it is very essential in arid and... 相似文献
262.
263.
Mehdi Amini Abbas Majdi Mohammad Amin Veshadi 《Rock Mechanics and Rock Engineering》2012,45(4):519-532
Block-flexure is the most common type of toppling failure in rock slopes. In this case, some rock blocks fail due to tensile bending stresses and some overturn under their own weights. In this paper, first, a literature review of toppling failures is summarized. Then, a theoretical model is proposed for rock slopes with a potential for block-flexure toppling instability. Next, a new analytical approach is presented for the stability analysis of such slopes. Finally, a special computer code is developed for a quick stability assessment of the failures based on the proposed method. This code receives the rock slope parameters from the user as the input data and predicts its stability, along with the corresponding factor of safety against the failure, as the output. In addition, two case studies are used for practical verification of the proposed approach and the corresponding computer code as well. 相似文献
264.
Mohammad KHANEHBAD Reza MOUSSAVI-HARAMI Asadollah MAHBOUBI Mehdi NADJAFI Mohammad Hosein MAHMUDY GHARAIE 《《地质学报》英文版》2012,86(5):1200-1210
Geochemical analysis of sandstones from the Sardar Formation (from two stratigraphic successions) in east-central Iran were used for identification of geochemical characterization of sandstones, provenance and tectonic setting. Sandstones in the two lithostratigraphic successions have similar chemical compositions suggesting a common provenance. Bulk-rock geochemistry analysis of Carboniferous sandstones from Sardar Formation indicates that they are mainly quartz dominated and are classified as quartzarenites, sublitharenites and subarkoses, derived from acid igneous to intermediate igneous rocks. Discrimination function analysis indicates that the sandstones of Sardar Formation were derived from quartzose sedimentary provenance in a recycled orogenic setting. Also, major and trace elements in sandstones of Sardar Formation (e.g., K2O/Na2O vs. SiO2) indicate deposition in a stable passive continental margin (PM). Chemical index of alteration (CIA) for these rocks (> 65%) suggests a moderate to relatively high degree of weathering in the source area. 相似文献
265.
Landfill site selection by decision-making tools based on fuzzy multi-attribute decision-making method 总被引:2,自引:2,他引:0
Abdolhadi Nazari Mohammad Mehdi Salarirad Abbas Aghajani Bazzazi 《Environmental Earth Sciences》2012,65(6):1631-1642
Landfill site selection is a complex and time-consuming process, which requires evaluation of several factors where many different
attributes are taken into account. Decision makers always have some difficulties in making the right decision in the multiple
attribute environments. After identifying candidate sites, these sites should be ranked using decision-making methods. This
study applies Chang’s fuzzy AHP-based multiple attribute decision-making (MADM) method for selection of the best site of landfills
based on a set of decision criteria. The Fuzzy Analytic Hierarchy Process (FAHP) was designed to make pairwise comparisons
of selected criteria by domain experts for assigning weights to the decision criteria. Analytic Hierarchy Process (AHP) is
used to make pairwise comparisons and assign weights to the decision criteria. It is easier for a decision maker to describe
a value for an alternative by using linguistic terms and fuzzy numbers. In the fuzzy-based AHP method, the rating of each
alternative was described using the expression of triangular fuzzy membership functions. Once the global weights of the criteria
is calculated by AHP, they are incorporated into the decision matrices composed by decision maker and passed to fuzzy-AHP
method which is used to determine preference order of siting alternatives. In this study, a computer program based on the
Chang’s fuzzy method was also developed in MATLAB environment for ranking and selecting the landfill site. As an example of
the proposed methodology, four different hypothetical areas were chosen and implemented to demonstrate the effectiveness of
the program. By using this program, the precision was improved in comparison with traditional methods and computational time
required for ranking and selecting the suitable landfill site was significantly reduced. 相似文献
266.
ABSTRACTWater infiltration into soils is an important component of hydrological processes. Direct measurement of infiltration is time consuming, expensive and often involves large spatial and temporal variability. The objective of this study was to develop and verify parametric pedotransfer functions (PTFs) to predict infiltration parameters. Consequently, 119 double-ring infiltration data were collected. The parameters of Philip, Kostiakov, Kostiakov-Lewis and Horton models were obtained, using the sum of squares error optimization method. Some parametric PTFs were then derived to predict the parameters of the infiltration models, using stepwise regression analysis. The results indicated a reasonable estimation of infiltration parameters by the derived PTFs. These results were more accurate when the land use of the studied area was considered. Overall results of this study suggest infiltration-based PTFs could be established as a reasonable indirect method for estimating infiltration parameters.
Editor M.C. Acreman; Associate editor N. Verhoest 相似文献
267.
Iranian earthquakes, a uniform catalog with moment magnitudes 总被引:3,自引:1,他引:2
Sepideh Karimiparidari Mehdi Zaré Hossein Memarian Andrzej Kijko 《Journal of Seismology》2013,17(3):897-911
A uniform earthquake catalog is an essential tool in any seismic hazard analysis. In this study, an earthquake catalog of Iran and adjacent areas was compiled, using international and national databanks. The following priorities were applied in selecting magnitude and earthquake location: (a) local catalogs were given higher priority for establishing the location of an earthquake and (b) global catalogs were preferred for determining earthquake magnitudes. Earthquakes that have occurred within the bounds between 23–42° N and 42–65° E, with a magnitude range of M W 3.5–7.9, from the third millennium BC until April 2010 were included. In an effort to avoid the “boundary effect,” since the newly compiled catalog will be mainly used for seismic hazard assessment, the study area includes the areas adjacent to Iran. The standardization of the catalog in terms of magnitude was achieved by the conversion of all types of magnitude into moment magnitude, M W, by using the orthogonal regression technique. In the newly compiled catalog, all aftershocks were detected, based on the procedure described by Gardner and Knopoff (Bull Seismol Soc Am 64:1363–1367, 1974). The seismicity parameters were calculated for the six main tectonic seismic zones of Iran, i.e., the Zagros Mountain Range, the Alborz Mountain Range, Central Iran, Kope Dagh, Azerbaijan, and Makran. 相似文献
268.
Feizollah Masoumi Taymour Eslamkish Mehdi Honarmand Ali Akbar Abkar 《Journal of the Indian Society of Remote Sensing》2017,45(6):1039-1055
This study attempts to evaluate the capability of the advanced spaceborne thermal emission and reflection radiometer (ASTER) and the advantages of ground knowledge for generating maps portraying hydrothermally altered areas in relation to porphyry copper deposits. The northern part of the Rabor area in the Urumieh–Dokhtar magmatic belt, containing some copper mineralization occurrences, was investigated as a case study. Several image processing techniques, namely minimum noise fraction, pixel purity index, and n-dimensional visualization, contributed to the extraction of pure pixels as endmembers. The spectra of some rock samples collected around the well-known altered zones of the study area were resampled to ASTER bands and used to identify the image-extracted endmembers. Spectral analysis of the endmembers and ground sample spectra led to the identification of three types of hydrothermal alterations: (1) phyllic, (2) propylitic, and (3) argillic. The identified endmembers were used as the specified targets for mapping hydrothermal alteration zones over the study area by using a mixture tuned match filtering algorithm. Results demonstrate that high abundances within pixels correspond closely to the altered areas. Field observations, thin section, and X-ray diffraction of collected samples confirmed the accuracy of the alteration maps prepared by the application of the proposed methods. The final classified hydrothermal alteration maps showed the overall accuracy and kappa coefficient values of 85.41 and 0.72%, respectively. These results ascertain that ASTER data that use suitable image processing techniques appear consistent in mapping out the distribution of hydrothermally altered areas. In addition, ground knowledge data can act as a valuable information source to increase the image classification accuracy and reliability. 相似文献
269.
Ali?Ben Dhiab Mehdi?Ben Mimoun Jose?OterosEmail author Herminia?Garcia-Mozo Eugenio?Domínguez-Vilches Carmen?Galán Mounir?Abichou Monji?Msallem 《Theoretical and Applied Climatology》2017,128(3-4):541-549
Tunisia is the world’s second largest olive oil-producing region after the European Union. This paper reports on the use of models to forecast local olive crops, using data for Tunisia’s five main olive-producing areas: Mornag, Jemmel, Menzel Mhiri, Chaal, and Zarzis. Airborne pollen counts were monitored over the period 1993–2011 using a Cour trap. Forecasting models were constructed using agricultural data (harvest size in tonnes of fruit/year) and data for several weather-related and phenoclimatic variables (rainfall, humidity, temperature, Growing Degree Days, and Chilling). Analysis of these data revealed that the amount of airborne pollen emitted over the pollen season as a whole (i.e., the Pollen Index) was the variable most influencing harvest size. Findings for all local models also indicated that the amount, timing, and distribution of rainfall (except during blooming) had a positive impact on final olive harvests. Air temperature also influenced final crop yield in three study provinces (Menzel Mhiri, Chaal, and Zarzis), but with varying consequences: in the model constructed for Chaal, cumulative maximum temperature from budbreak to start of flowering contributed positively to yield; in the Menzel Mhiri model, cumulative average temperatures during fruit development had a positive impact on output; in Zarzis, by contrast, cumulative maximum temperature during the period prior to flowering negatively influenced final crop yield. Data for agricultural and phenoclimatic variables can be used to construct valid models to predict annual variability in local olive-crop yields; here, models displayed an accuracy of 98, 93, 92, 91, and 88 % for Zarzis, Mornag, Jemmel, Chaal, and Menzel Mhiri, respectively. 相似文献
270.
Nima Akbari Paydar Mohammad Mehdi Ahmadi 《Geotechnical and Geological Engineering》2016,34(6):1857-1876
The use of shear wave velocity (V s) measurements as an in situ test for evaluation of liquefaction potential has increased substantially due to its advantages. Relatively large numbers of studies have been performed to establish the correlation between V s and liquefaction resistance (CRR) of clean sands. Usually, natural sands contain silt and/or clay, and previous studies have shown that both the amount of fines and their nature influence the values of CRR as well as V s. Therefore, the CRR–V s correlations may also be affected by fines content and type of sandy soils. However, effect of fines content and especially fines type of sandy soils on the correlation between V s and CRR is inadequately addressed in the literature. In this study, cyclic triaxial and bender element tests were conducted on samples of sand containing various amounts of different types of fines, and the effects of fines on the values of CRR and V s are investigated. The results show that G 0 and CRR reduce even when small amounts of fines are added to sand. Therefore, use of plasticity index (PI) of the fines fraction is better than the PI of the overall soil when trying to assess the effects of fines. Using obtained experimental data as well as the established semiempirical CRR–V s relationship, the CRR–V s correlation was developed for all the tested soils, and the effect of fines type on the correlation is also examined. Based on the results obtained in this study, CRR–V s correlation is affected by both the amount and the plasticity of the fines present in the sand, and this correlation is soil specific. 相似文献