排序方式： 共有73条查询结果，搜索用时 15 毫秒
21.
Boroomandnia Arezoo Bozorg-Haddad Omid Bahrami Mahdi Goharian Erfan Singh Vijay P. Lo&#;iciga Hugo A. 《Hydrogeology Journal》2021,29(4):1379-1398
Hydrogeology Journal - A coupled simulation-optimization model (SOM) is developed in this work that links the US Environmental Protection Agency’s Storm Water Management Model (SWMM) with a... 相似文献
22.
Spatial prediction of flood-susceptible areas using frequency ratio and maximum entropy models 总被引：1，自引：0，他引：1
Modelling the flood in watersheds and reducing the damages caused by this natural disaster is one of the primary objectives of watershed management. This study aims to investigate the application of the frequency ratio and maximum entropy models for flood susceptibility mapping in the Madarsoo watershed, Golestan Province, Iran. Based on the maximum entropy and frequency ratio methods as well as analysis of the relationship between the flood events belonging to training group and the factors affecting on the risk of flooding, the weight of classes of each factor was determined in a GIS environment. Finally, prediction map of flooding potential was validated using receiver operating characteristic (ROC) curve method. ROC curve estimated the area under the curve for frequency ratio and the maximum entropy models as 74.3% and 92.6%, respectively, indicating that the maximum entropy model led to better results for evaluating flooding potential in the study area. 相似文献
23.
Omid Sayar Iman Jabbari Zahir Abadi Omid Sadeghi Hamid Reza Lotfi Zadeh Zhad Najmeh Tavassoli 《洁净——土壤、空气、水》2012,40(3):272-277
Nano‐alumina modified by 9‐aminoacridine was used as a sorbent for separation and determination of dichromate ions from water. Statistical method, based on surface response design, has been used for the optimization of dichromate ions elution from 9‐aminoacridine nano‐alumina. The adsorbed dichromate ions were found to be eluted quantitatively with 0.8 mol L?1 KCl in 1.6 mol L?1 NaOH which optimized by response surface design. Under optimum conditions, the accuracy, precision (relative standard deviation, RSD%) and R‐square of the method were calculated as >98, <3, and >94%, respectively. Remarkable agreement between experimental and theoretical data was confirmed the predicted assumption. The method was applied to the simultaneous determination of dichromate in natural and industrial water samples. We also examined the retention of dichromate anions in the presence of Cl?, , and anions at pH 3. 相似文献
24.
Multiple-point geostatistical simulation of dykes: application at Sungun porphyry copper system,Iran 总被引：5，自引：3，他引：2
Hassan Rezaee Omid Asghari Mohammad Koneshloo Julián M. Ortiz 《Stochastic Environmental Research and Risk Assessment (SERRA)》2014,28(7):1913-1927
Variogram-based methods are not capable of capturing high (>2) order statistics since the variogram measures the relationship between two points at a time only. Multiple-point geostatistics (MPS) has brought new insights into many geological modeling problems. The application of MPS methods has been well documented in realizing complex geological patterns. These methods have often been used in reservoir characterization since their advent in recent decades. The frequent non-linear behaviors of geologic continuity are not limited to reservoirs, but mineral deposits bear complicated formations in many cases. Relying on the power of MPS methods and considering the complexity of geological scenarios in mineral deposits, we have applied MPS in the modeling of mineral deposits. A training image (TI) is produced using geological data from upper horizons of a porphyry copper ore deposit which have been mined out during the previous mining operations. In this study, the SNESIM algorithm has been used. A number of realizations are produced using this multiple-point geostatistical method. Extensive validation steps are performed considering the TI as the reference model. These validations first show that the TI is representative for the domain under study and also illustrates some degrees of similarity between the TI and the realizations. Despite simplifications made to the problem, the application of MPS in mineral deposit modeling still faces many challenges. 相似文献
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26.
S. Amir Reza Beyabanaki Ahmad Jafari S. Omid Reza Biabanaki M. Ronald Yeung 《Computers and Geotechnics》2009
This paper presents a new numerical model that can add a finite element mesh into each block of the three-dimensional discontinuous deformation analysis (3-D DDA), originally developed by Gen-hua Shi. The main objectives of this research are to enhance DDA block’s deformability. Formulations of stiffness and force matrices in 3-D DDA with conventional Trilinear (8-node) and Serendipity (20-node) hexahedral isoparametric finite elements meshed block system due to elastic stress, initial stress, point load, body force, displacement constraints, inertia force, normal and shear contact forces are derived in detail for program coding. The program code for the Trilinear and Serendipity hexahedron elements have been developed, and it has been applied to some examples to show the advantages achieved when finite element is associated with 3-D DDA to handle problems under large displacements and deformations. Results calculated for the same models by use of the original 3-D DDA are far from the theoretical solutions while the results of new numerical model are quite good in agreement with theoretical solutions; however, for the Trilinear elements, more number of elements are needed. 相似文献
27.
Beyranvand Azar Azizi Ghasem Alizadeh-Choobari Omid Darvishi Boloorani Ali 《Natural Hazards》2019,98(1):229-249
Large near-field tsunamis pose a significant threat to the Canadian West Coast due to its proximity to the circum-Pacific belt where a significant tsunami-inducing earthquake event from the Cascadia subduction zone is expected. This study investigated the risks associated with such an event in terms of pedestrian evacuation needs and plans for the Town of Tofino, a small community located on the West Coast of Vancouver Island. The population-at-risk within the hazard zone and its ability to evacuate to safety is evaluated using anisotropic path-distance modelling. Mitigation measures, such as vertical evacuation buildings, are quantitatively evaluated. Site-specific inundation modelling was not performed as part of this study; tsunami hazard and safe zones were computed using a range of run-ups varying between 3 and 25 m. It was established that up to 80% of the population is within the maximum hazard zone considered. This evacuation modelling exercise indicates that a maximum of 13% of the population would have insufficient time to reach safety when using a mobility-impaired ambulatory speed. The use of three vertical evacuation buildings can reduce the risk of losing population in this category by 99%. Although some conservative assumptions were used (vertical datum at higher high water, reductions in safe zones by generalization process and mobility-impaired evacuation speeds), the evacuation potential is likely overestimated due to the coarseness of the topographic data used in the evacuation modelling and from an overestimated first wave arrival time. This is the first Canadian study which used anisotropic evacuation modelling to evaluate the vulnerability of a Canadian community to tsunami inundation.
相似文献28.
Hajsadeghi Saeid Asghari Omid Mirmohammadi Mirsaleh Meshkani Seyed Ahmad 《Natural Resources Research》2020,29(1):161-171
Natural Resources Research - Multivariate methods are useful for simplifying the interpretation of variables in geochemical data and are widely used to uncover relationships between elements that... 相似文献
29.
Mahdi Panahi Abolfazl Jaafari Ataollah Shirzadi Himan Shahabi Omid Rahmati Ebrahim Omidvar Saro Lee Dieu Tien Bui 《地学前缘(英文版)》2021,12(3):370-383
Flood probability maps are essential for a range of applications, including land use planning and developing mitigation strategies and early warning systems. Th... 相似文献
30.
Applicability of generalized additive model in groundwater potential modelling and comparison its performance by bivariate statistical methods 总被引：3，自引：0，他引：3
Fatemeh Falah Samira Ghorbani Nejad Omid Rahmati Mania Daneshfar Hossein Zeinivand 《国际地球制图》2017,32(10):1069-1089
Groundwater is the most valuable natural resource in arid areas. Therefore, any attempt to investigate potential zones of groundwater for further management of water supply is necessary. Hence, many researchers have worked on this subject all around the world. On the other hand, the Generalized Additive Model (GAM) has been applied to environmental and ecological modelling, but its applicability to other kinds of predictive modelling such as groundwater potential mapping has not yet been investigated. Therefore, the main purpose of this study is to evaluate the performance of GAM model and then its comparison with three popular GIS-based bivariate statistical methods, namely Frequency Ratio (FR), Statistical Index (SI) and Weight-of-Evidence (WOE) for producing groundwater spring potential map (GSPM) in Lorestan Province Iran. To achieve this, out of 6439 existed springs, 4291 spring locations were selected for training phase and the remaining 2147 springs for model evaluation. Next, the thematic layers of 12 effective spring parameters including altitude, plan curvature, slope angle, slope aspect, drainage density, distance from rivers, topographic wetness index, fault density, distance from fault, lithology, soil and land use/land cover were mapped and integrated using the ArcGIS 10.2 software to generate a groundwater prospect map using mentioned approaches. The produced GSPMs were then classified into four distinct groundwater potential zones, namely low, moderate, high and very high classes. The results of the analysis were finally validated using the receiver operating characteristic (ROC) curve technique. The results indicated that out of four models, SI is superior (prediction accuracy of 85.4%) following by FR, GAM and WOE, respectively (prediction accuracy of 83.7, 77 and 76.3%). The result of groundwater spring potential map is helpful as a guide for engineers in water resources management and land use planning in order to select suitable areas to implement development schemes and also government entities. 相似文献