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Building damage maps after disasters can help us to better manage the rescue operations. Researchers have used Light Detection and Ranging (LiDAR) data for extracting the building damage maps. For producing building damage maps from LiDAR data in a rapid manner, it is necessary to understand the effectiveness of features and classifiers. However, there is no comprehensive study on the performance of features and classifiers in identifying damaged areas. In this study, the effectiveness of three texture extraction methods and three fuzzy systems for producing the building damage maps was investigated. In the proposed method, at first, a pre-processing stage was utilized to apply essential processes on post-event LiDAR data. Second, textural features were extracted from the pre-processed LiDAR data. Third, fuzzy inference systems were generated to make a relation between the extracted textural features of buildings and their damage extents. The proposed method was tested across three areas over the 2010 Haiti earthquake. Three building damage maps with overall accuracies of 75.0%, 78.1% and 61.4% were achieved. Based on outcomes, the fuzzy inference systems were stronger than random forest, bagging, boosting and support vector machine classifiers for detecting damaged buildings.  相似文献   
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Natural Hazards - The Kazerun fault system (KFS) is located in the central part of the Zagros, the most seismically active orogenic belt in the Iranian plateau. The city of Yasouj is located in the...  相似文献   
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Geotechnical and Geological Engineering - The effects of diameter and location of drain pipes on the uplift force and exit hydraulic gradient for a gravity dam are investigated. A numerical model...  相似文献   
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The Oligocene–Miocene Asmari Formation of the Zagros Basin is a thick sequence of shallow water carbonate. In the study area, it is subdivided into 14 microfacies that are distinguished on the basis of their depositional textures, petrographic analysis and fauna. Based on the paleoecology and lithology, four distinct depositional settings can be recognized: tidal flat, lagoon, barrier, and open marine. The Asmari Formation represents sedimentation on a carbonate ramp. In the inner ramp, the most abundant lithofacies are medium grained wackestone–packstone with imperforated foraminifera. The middle ramp is represented by packstone–grainstone to floatstone with a diverse assemblage of larger foraminifera with perforate wall, red algae, bryozoa, and echinoids. The outer ramp is dominated by argillaceous wackestone characterized by planktonic foraminifera and large and flat nummulitidae and lepidocyclinidae. Three third-order depositional sequences are recognized from deepening and shallowing trends in the depositional facies, changes in cycle stacking patterns, and sequence boundary features.  相似文献   
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This paper focuses on the Qareh Sou Basin in Golestan Province, Iran. Golestan Province is the third largest cereal producer in Iran and water scarcity and salinity are major problems in this area. This study attempts to facilitate the comprehension of system behavior with respect to water quality issues and hydro-geochemical coefficients within the Qareh Sou Basin. This study was carried out during the year 2010. Various parameters, such as pH, EC, chloride, sulfate, bicarbonate, sodium, potassium, calcium and magnesium have been determined for evaluation purposes. Then, Ca/Mg, Na/Cl, Mg/(Ca + Mg), Ca/HCO3, (Ca + Mg)–(HCO3 + SO4), (Na + K)–Cl, (Ca + Mg + Na + K)–Cl, HCO3 + SO4, Ca + Mg and chloro-alkaline indices (CAI) were calculated. Results show that cation exchange probably is an important factor in the hydrochemistry and silicate mineral weathering. Also, CAI-1 plot against CAI-2 demonstrates that most of samples have positive values which suggest normal ion exchange in the system. The carbonic acid is the main agent of calcite, limestone and dolomite weathering which occurs in some stations. According to Chadha’s diagram, the type of water is determined as Ca–Mg–HCO3.  相似文献   
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Ommi  Salma  Janalipour  Milad 《Natural Hazards》2022,113(1):345-363
Natural Hazards - After a major earthquake, one of the main tasks is to identify temporary shelters. In this study, we utilized probabilistic aftershock hazard analysis based on land use...  相似文献   
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For many decades most oil wells in Iran have produced using their natural flow potential and haven’t needed to be fractured. As time goes by, the reservoir pressure depletes and the need for hydraulic fracturing as a stimulation practice arises. Nonetheless there is no record of successful hydraulic fracturing in Iran.

The Bangestan reservoir with a suitable amount of oil in place and good rock reservoirs, has been selected for the present research work. In this work, the in situ stress profile was calculated by using the available petrophysical data. This is achieved by using poroelastic theory for the stresses, and the Mohr–Coulomb criterion to predict failure. The model leads to easily computed expressions for calculating the pressure required to maintain hydraulic fracturing. Then the appropriate depth for treatment was determined. The results indicate that Ilam and Sarvak formations could be good candidates for hydraulic fracturing. Then, for two layers, a hydraulic fracture was designed and the production was predicted and the Net Present Value (NPV) resulting from the fracture of both layers was investigated.  相似文献   

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Stochastic Environmental Research and Risk Assessment - Organizations are continuously endeavoring to provide a healthy work environment without any incident, by Health, Safety, and Environment...  相似文献   
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Detailed local geological, geophysical, and hydrogeological investigations were carried out for the alluvial aquifer in the Kangavar basin, West Iran to delineate the architecture of different subsurface geological horizons using lithologs and generated vertical electrical sounding (VES) data. An attempt has also been made to estimate aquifer transmissivity from resistivity data. Forty VESs were recorded with the Schlumberger electrode configuration in the study area; 28 of these were selected for evaluation. The maximum current electrode spacing was 400–500 m. The data obtained were interpreted by computer iterative modeling with curve matching for calibration purposes. In order to ascertain the subsurface geological framework, the general distribution of resistivity responses of the geological formations was obtained and geoelectrical sections along a number of lines were prepared. Probable aquifer horizons from these sections were identified. The transmissivity of the unconfined aquifer was computed by determining the Dar-Zarrouk parameters (longitudinal unit conductance and transverse unit resistance) and were compared with the actual field transmissivity. The results showed a direct relation between aquifer transmissivity and modified transverse resistance.  相似文献   
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