Risk Analysis and Prediction of Floor Failure Mechanisms at Longwall Face in Parvadeh-I Coal Mine using Rock Engineering System (RES)     

Sajjad Aghababaei  Gholamreza Saeedi  Hossein Jalalifar 《Rock Mechanics and Rock Engineering》2016,49(5):1889-1901

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Soil erosion prediction based on land cover dynamics at the Semenyih watershed in Malaysia using LTM and USLE models   总被引：1，自引：0，他引：1  

Hossein Mojaddadi Rizeei  Maryam Adel Saharkhiz  Noordin Ahmad 《国际地球制图》2016,31(10):1158-1177

This study attempts to identify and forecast future land cover (LC) by using the Land Transformation Model (LTM), which considers pixel changes in the past and makes predictions using influential spatial features. LTM applies the Artificial Neural Networks algorithm) in conducting the analysis. In line with these objectives, two satellite images (Spot 5 acquired in 2004 and 2010) were classified using the Maximum Likelihood method for the change detection analysis. Consequently, LC maps from 2004 to 2010 with six classes (forest, agriculture, oil palm cultivations, open area, urban, and water bodies) were generated from the test area. A prediction was made on the actual soil erosion and the soil erosion rate using the Universal Soil Loss Equation (USLE) combined with remote sensing and GIS in the Semenyih watershed for 2004 and 2010 and projected to 2016. Actual and potential soil erosion maps from 2004 to 2010 and projected to 2016 were eventually generated. The results of the LC change detections indicated that three major changes were predicted from 2004 to 2016 (a period of 12 years): (1) forest cover and open area significantly decreased at rates of almost 30 and 8 km², respectively; (2) cultivated land and oil palm have shown an increment in sizes at rates of 25.02 and 5.77 km², respectively; and, (3) settlement and Urbanization has intensified also by almost 5 km². Soil erosion risk analysis results also showed that the Semenyih basin exhibited an average annual soil erosion between 143.35 ton ha^?1 year^?1 in 2004 and 151 in 2010, followed by the expected 162.24 ton ha^?1 year^?1. These results indicated that Semenyih is prone to water erosion by 2016. The wide range of erosion classes were estimated at a very low level (0–1 t/ha/year) and mainly located on steep lands and forest areas. This study has shown that using both LTM and USLE in combination with remote sensing and GIS is a suitable method for forecasting LC and accurately measuring the amount of soil losses in the future.  相似文献   

Effect of dry density,soil texture and time-spatial variable water content on the soil thermal conductivity     

Saeid Nikoosokhan  Hossein Nowamooz  Cyrille Chazallon 《Geomechanics and Geoengineering》2016,11(2):149-158

Study of the heat transfer process in saturated and unsaturated soils requires, basically, a relationship between thermal conductivity and the characteristics of the soil, such as water content, dry density and texture of the soil. This study intends to produce a generic model that can predict soil thermal conductivity with the help of easily measurable parameters. The proposed model is first calibrated using measured thermal conductivities from literature data. In order to validate the proposed model the predicted thermal conductivity of this proposed model as well as existing ones are compared with the measured thermal conductivity in literature for different soils. Validation of the proposed model was also performed on our experimental results obtained for a compacted Misillac sand and in-situ clay loam soils. The results show an average of 15% improvement in prediction accuracy for the proposed model compared to the existing models, considering all soil textures. Moreover, we perform a model to estimate thermal conductivity over time throughout the profile of soil in the context of seasonal variation of temperature. The proposed model shows an important effect of heterogeneity on the thermal conductivity variations of a double layered soil.  相似文献   

Modeling landfill site selection by multi-criteria decision making and fuzzy functions in GIS,case study: Shabestar,Iran     

Sara Bahrani  Taghi Ebadi  Hadi Ehsani  Hossein Yousefi  Reza Maknoon 《Environmental Earth Sciences》2016,75(4):337

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Influence of introducing various meteorological parameters to the Angström–Prescott model for estimation of global solar radiation     

Kasra Mohammadi  Hossein Khorasanizadeh  Shahaboddin Shamshirband  Chong Wen Tong 《Environmental Earth Sciences》2016,75(3):219

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Poisson distribution of the Iranian declustered earthquake catalog     

Mehdi Zare  Sepideh Karimiparidari  Hossein Memarian  Farnaz Kamranzad 《Arabian Journal of Geosciences》2016,9(19):737

Two main goals are considered in this paper: (1) modification and computation of the local coefficients of the space-time windows in the well-known declustering algorithm introduced by Gardner and Knopoff (1974) and (2) checking the independence of the Iranian mainshocks obtained from applying the new modified model. First, 21 of the well-documented earthquake sequences of Iran in the time period of 1972 to 2008 with the mainshock magnitude ranged from M _w = 5.4–7.1 were used to define the new local space-time windows of declustering. Generally, using these Iranian earthquake sequences led to introduce bigger space-time windows for the new model in comparison to the Gardner and Knopoff’s (1974) windows. In the next step, to control the independence of Iranian mainshocks, the events of the Iranian earthquake catalog in the time span of 1964–2010 with moment magnitude of M _w = 3.5–7.4 were used. In this respect, dependent events corresponding to the seven seismotectonic zones of Iran were removed using the new modified space-time windows. After declustering, the mainshock catalog was examined by the Kolmogorov–Smirnov goodness-of-fit test, and it was found to follow a Poisson distribution in all the studied seismotectonic zones of Iran. The same test on times between successive declustered events shows that the inter-event times of all catalogs follow an exponential distribution.  相似文献   

Iranian ultrapotassic volcanism at ~11 Ma signifies the initiation of post‐collisional magmatism in the Arabia–Eurasia collision zone     

Kwan‐Nang Pang  Sun‐Lin Chung  Mohammad Hossein Zarrinkoub  Yu‐Chin Lin  Hao‐Yang Lee  Ching‐Hua Lo  Mohammad Mahdi Khatib 《地学学报》2013,25(5):405-413

Ultrapotassic rocks are a common, but volumetrically minor, hallmark of post‐collisional magmatism along the Alpine–Himalayan orogenic belt. Here, we document the occurrence of ultrapotassic volcanic rocks from the Eslamy peninsula, NW Iran in the Arabia–Eurasia collision zone. Our results indicate that magma genesis involved melting of phlogopite‐ and apatite‐bearing peridotites in the sub‐continental lithospheric mantle at ~11 Ma. These peridotites likely formed by metasomatism involving components derived from subducted sediments during Neotethyan subduction. The ~11 Ma ultrapotassic volcanism was preceded by a magmatic gap of ~11 Ma after the cessation of arc magmatism in NW Iran and Armenia, thus likely representing the initiation of post‐collisional magmatism. The age coincides with the onset of collision‐related magmatic activity and topographic uplift in the Caucasus–Iran–Anatolia region, and also with other regional geological events including the closure of the eastern Tethys gateway, the end of Arabian underthrusting and the start of escape tectonics in Anatolia.  相似文献   

Extreme streamflow drought in the Karkheh river basin (Iran): probabilistic and regional analyses     

Reza Zamani  Hossein Tabari  Patrick Willems 《Natural Hazards》2015,76(1):327-346

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Parking Lot Site Selection: An Opening Gate Towards Sustainable GIS-based Urban Traffic Management     

Kazem Aliniai  Asad Yarahmadi  Jaleh Zang Zarin  Hossein Yarahmadi  Shahram Bakhtiari Lak 《Journal of the Indian Society of Remote Sensing》2015,43(4):801-813

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Effect of non‐uniformity of flow on velocity and turbulence intensities over a cobble‐bed     

Hossein Afzalimehr 《水文研究》2010,24(3):331-341

Non‐uniform flows encompassing both accelerating and decelerating flows over a cobble‐bed flume have been experimentally investigated in a flume at a scale of intermediate relative submergence. Measurements of mean longitudinal flow velocity u, and determinations of turbulence intensities u′, v′, w′, and Reynolds shear stress ?u_fw_f have been made. The longitudinal velocity distribution was divided into the inner zone close to the bed and the outer zone far from the bed. In the inner zone of the boundary layer (near the bed) the velocity profile closely followed the ‘Log Law’; however, in the outer zone the velocity distribution deviated from the Log Law consistently for both accelerating and decelerating flows and the changes in bed slopes ranging from ?2% to + 2% had no considerable effect on the outer zone. For a constant bed slope (S = ±0·015), the larger the flow rate, the smaller the turbulence intensities. However, no detectable pattern has been observed for u′, v′ and w′ distributions near the bed. Likewise, for a constant flow rate (Q = 0·040 m³/s), with variation in bed slope the longitudinal turbulent intensity profile in the longitudinal direction remained concave for both accelerating and decelerating flows; whereas vertical turbulent intensity (w′) profile presented no specific form. The results reveal that the positions of maximum values of turbulence intensities and the Reynolds shear stress depend not only on the flow structure (accelerating or decelerating) but also on the intermediate relative submergence scale. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献