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131.
Natural Hazards - Hydrological modeling academic studies have focused on the response to human-caused land use changes. The effects of land use change on flood degree in the catchment basin of... 相似文献
132.
Naghizade Asl Fateme Asgari Hamid Reza Emami Hojat Jafari Mohammad 《Geotechnical and Geological Engineering》2021,39(5):3347-3360
Geotechnical and Geological Engineering - Mulching is fastest strategy to control sand dune movement in arid and semiarid areas. In the present study the effect of micro silica- cement mixture was... 相似文献
133.
Shahverdiloo Mohammad Reza Zare Shokrollah 《Geotechnical and Geological Engineering》2021,39(8):5517-5528
Geotechnical and Geological Engineering - All numerical and analytical methods dealing with the calculating deformation of rock mass require deformation modulus (Df) which is measured by direct or... 相似文献
134.
Hamid Reza Pakzad 《Astrophysics and Space Science》2009,323(4):345-350
In this paper, the characteristics of ion acoustic solitary waves are studied in plasmas containing warm ion fluid, non-thermally
distributed electron and positron. We study the effects of non-thermal electrons and ion temperature on solitons by Pseudo-potential
method and show that the parametric region where ion acoustic solitons can exist is modified. We also obtain linear dispersion
relation by using the standard normal-modes analysis. 相似文献
135.
136.
A real-time operation optimization model for flood management in river-reservoir systems 总被引:1,自引:1,他引:0
In this paper, a new methodology has been developed for real-time flood management in river-reservoir systems. This methodology
is based upon combining a Genetic Algorithm (GA) reservoir operation optimization model for a cascade of two reservoirs, a
hydraulic-based flood routing simulation model in downstream river system, a Geographical Information System (GIS) based database,
and application of K-Nearest Neighbor (K-NN) algorithm for development of optimal operating rules. The GA optimization model
estimates the optimal hourly reservoirs’ releases to minimize the flood damages in the downstream river. GIS tools have also
been used for specifying different land-uses and damage functions in the downstream floodplain and it has been linked to the
unsteady module of HEC-RAS flood routing model using Hec-GeoRAS module. An innovative approach has also been developed using
K-NN algorithm to formulate the optimal operating rules for a system of two cascade reservoirs based on optimal releases obtained
from the optimization model. During a flood event, the K-NN algorithm searches through the historical flood hydrographs and
optimal reservoir storages determined by the optimization model to find similar situations. The similarity between the hydrographs
is quantified based on the slopes of rising and falling limbs of inflow hydrographs and reservoir storages at the beginning
of each hourly time step during the flood events for two cascade reservoirs. The developed methodology have been applied to
the Bakhtiari and Dez River-Reservoir systems in southwest of Iran. The results show that the proposed models can be effectively
used for flood management and real-time operation of cascade river-reservoir systems. 相似文献
137.
138.
139.
Ali Reza Keyvani Boroujeni Majid Sadeghazar 《地震工程与工程振动(英文版)》2006,5(2):297-307
The Iranian Guideline for Seismic Rehabilitation of Existing Buildings (GSREB), which is currently used for vulnerability assessment of existing buildings in Iran, is evaluated in this paper. The vulnerability of sample buildings of a variety stories with special steel moment resisting frames, designed according to the Standard No.2800 requirements, is assessed by GSREB. In the vulnerability assessment, different analysis methods were used and the results, in terms of usage ratio, defined as the ratio of the strength/deformation demand to the corresponding capacity, are compared. Numerical results show that some columns of these buildings do not satisfy the life safety performance criteria in the design hazard level. Moreover, the target displacement estimated by the Displacement Coefficient Method (DCM) is larger than the maximum displacement calculated by nonlinear dynamic analysis. 相似文献
140.
Nader Davoudi Hamid Reza Tavakoli Mehdi Zare Abdollah Jalilian 《Acta Geophysica》2018,66(6):1359-1373
The main goal of this article is to decluster Iranian plateau seismic catalog by the epidemic-type aftershock sequence (ETAS) model and compare the results with some older methods. For this purpose, Iranian plateau bounded in 24°–42°N and 43°–66°E is subdivided into three major tectonic zones: (1) North of Iran (2) Zagros (3) East of Iran. The extracted earthquake catalog had a total of 6034 earthquakes (Mw?>?4) in the time span 1983–2017. The ETAS model is an accepted stochastic approach for seismic evaluation and declustering earthquake catalogs. However, this model has not yet been used to decluster the seismic catalog of Iran. Until now, traditional methods like the Gardner and Knopoff space–time window method and the Reasenberg link-based method have been used in most studies for declustering Iran earthquake catalog. Finally, the results of declustering by the ETAS model are compared with result of Gardner and Knopoff (Bull Seismol Soc Am 64(5):1363–1367, 1974), Uhrhammer (Earthq Notes 57(1):21, 1986), Gruenthal (pers. comm.) and Reasenberg (Geophys Res 90:5479–5495, 1985) declustering methods. The overall conclusion is difficult, but the results confirm the high ability of the ETAS model for declustering Iranian earthquake catalog. Use of the ETAS model is still in its early steps in Iranian seismological researches, and more parametric studies are needed. 相似文献