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1.
Nader Saadatkhah Mohammadreza Hadad Tehrani Shattri Mansor Zailani Khuzaimah Azman Kassim Reza Saadatkhah 《Arabian Journal of Geosciences》2016,9(17):687
In the current years, changing the land cover/land use had serious hydrological impacts affecting the flood events in the Kelantan River basin. The flood events at the east coast of the peninsular Malaysia got highly affected in the recent decades due to several factors like urbanisation, rapid changes in the utilisation of land and lack of meteorological (i.e. change in climate) and developmental monitoring and planning. The Kelantan River basin has been highly influenced due to a rapid change in land use during 1984 to 2013, which occurred in the form of transformation of agricultural area and deforestation (logging activities). In order to evaluate the influence of the modifications in land cover on the flood events, two hydrological regional models of rainfall-induced runoff event, the Hydrologic Engineering Center (HEC)-Hydrologic Modeling System (HMS) model and improved transient rainfall infiltration and grid-based regional model (Improved TRIGRS), were employed in this study. The responses of land cover changes on the peak flow and runoff volume were investigated using 10 days of hourly rainfall events from 20 December to the end of December 2014 at the study area. The usage of two hydrological models defined that the changes in land use/land cover caused momentous changes in hydrological response towards water flow. The outcomes also revealed that the increase of severe water flow at the study area is a function of urbanisation and deforestation, particularly in the conversion of the forest area to the less canopy coverage, for example, oil palm, mixed agriculture and rubber. The monsoon season floods and runoff escalate in the cleared land or low-density vegetation area, while the normal flow gets the contribution from interflow generated from secondary jungle and forested areas. 相似文献
2.
Behzad Khani Mohammadreza Kamali Maryam Mirshahani Mahmood Memariani Mahmood Bargrizan 《Arabian Journal of Geosciences》2018,11(2):39
The Upper Jurassic Sargelu and the Cretaceous Garau formations are important source rocks in the Lurestan basin, southwest Iran. In this study, the maturity evolution and burial history of these source rocks are investigated using 1D modeling in 15 wells within the Lurestan basin. These models are calibrated using temperature and vitrinite reflectance readings at well locations. Results indicate that thermal maturity of studied source rocks increases towards the northwest of the Lurestan basin and is the lowest over the Anaran High. The present-day level of maturity suggests that these formations are suitable candidates for shale gas resources in the Lurestan basin. 相似文献
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Taherynia Mohammad Hossein Koopialipoor Mohammadreza Azizzadeh Abbas Fahimifar Ahmad Ghyasvand Soheil 《Geotechnical and Geological Engineering》2021,39(7):5119-5133
Geotechnical and Geological Engineering - Small variation in shear strength parameters results in remarkable changes in the safety factor (SF) of a rock slope. In this regard, rock mass strength of... 相似文献
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In this paper, we describe the computational framework of a novel method for solving the challenging problem of probabilistic
finite elements. The method is called Improved Dynamic Bounds (IDB) and was developed recently to improve the efficiency of
the dynamic bounds. The IDB is used in finite element numerical models to calculate time-dependent failure analyses of structures.
In applications, the IDB can speed up the overall simulation process by several orders of magnitude. In applications controlled
by two influential variables (e.g, two-dimensional problem), the computational efficiency is improved by a factor of 769 according
to Rajabalinejad (2009). Applications of IDB indicate the method is most efficient for problems where the number of influential variables are limited.
This is often the case for geotechnical and coastal flood defence systems. The IDB method is applied in this paper to the
17th Street Flood Wall, a component of the flood defence system (levee infra-structure) that failed during the Hurricane Katrina,
to calculate the failure probability of an I-wall. 相似文献
5.
Making use of the homogenization method for periodic media, developed in the context of elastoplasticity, a simplified constitutive law is proposed for a stone column-reinforced soil, regarded as a homogeneous but anisotropic medium. The closed-form expressions derived for such a constitutive law allow for its implementation into a f.e.m-based numerical procedure. The computational code so obtained is then applied to simulating the response of a foundation soil reinforced by a group of floating columns, expressed in terms of load–settlement curves drawn up to the ultimate bearing capacity. 相似文献
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Agricultural use of soils implies tillage and often compaction and therefore influences processes on soil surface and affects infiltration of water into the subsoil. Although many studies on soil surface processes or flow patterns in soils exist, works relating both are rare in literature. We did two tracer experiments with Brilliant Blue FCF on a tilled and compacted plot and a non‐tilled one to investigate water storage on the soil surface during simulated rainfall and changes of soil microtopography, to analyse the associated flow patterns in the soil and to relate both to tillage and compaction. Our results show that storage was larger on the tilled and compacted plot than on the non‐tilled one. After tillage, transport processes above the plough pan were partly disconnected from those underneath because macropores were disrupted and buried by the tillage operation. However, preferential flow along cracks occurred on both plots and the macropores buried below the tillage pan still functioned as preferential flow paths. Therefore, we conclude that the studied soil is susceptible to deep vertical solute propagation at dry conditions when cracks are open, irrespective of tillage and compaction. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
7.
Generalization and spatial contextual awareness are prevalent concepts in geographic information systems. This study adopted a context-dependent user-centred network generalization method to create a sub-network for optimal route finding. The results show an increase in the number of preferred traversed edges. A route presentation approach is suggested that is based on cognitively engineered user-oriented abstraction of street network. Successive abstractions hierarchize the street network to create a hierarchical presentation structure. The route is projected onto one level in the structure. Then, instead of showing the exact route, the network Voronoi regions represented by the projected route are shown. Experience indicates that the suggested method is an efficient way of route presentation for a hierarchical regionalized structure of a human cognitive map. 相似文献
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A model for the air–sea interface, based on the coupled pair of similarity relations for “aerodynamically” rough flow in both
fluids, is presented, which is applied to fetch-limited and high wind speed conditions which occur, for example, in hurricanes.
It is shown that the specification of the maximum 10-m drag coefficient and the 10-m wind speed and the peak wave speed at
which it occurs are sufficient to uniquely determine the drag law, which asymptotes at low wind speeds to a Charnock constant
similar to that for the fully developed wind wave sea and is almost independent of the peak wave speed at the maximum in drag
coefficient. A feature of the drag law is that it is of Charnock form, almost independent of the wave age, consistent with
the transfer of momentum to the wave spectrum being due to the smaller rather than the dominant wavelengths. The analysis
is also applied to a variable sea state in which either the surface wind or the surface Stokes drift vary, but the peak wave
speed is kept constant. The corresponding variability in the Charnock constant is in general accord with observations. 相似文献