Zoning map for drought prediction using integrated machine learning models with a nomadic people optimization algorithm     

Mohamadi  Sedigheh  Sammen  Saad Sh.  Panahi  Fatemeh  Ehteram  Mohammad  Kisi  Ozgur  Mosavi  Amir  Ahmed  Ali Najah  El-Shafie  Ahmed  Al-Ansari  Nadhir 《Natural Hazards》2020,104(1):537-579

Natural Hazards - The modelling of drought is of utmost importance for the efficient management of water resources. This article used the adaptive neuro-fuzzy interface system (ANFIS), multilayer...  相似文献   

Monthly precipitation assessments in association with atmospheric circulation indices by using tree-based models     

Sattari  Mohammad Taghi  Shaker Sureh  Fatemeh  Kahya  Ercan 《Natural Hazards》2020,102(3):1077-1094

Natural Hazards - The Urmia Lake basin is one of the most important basins in Iran, facing many problems due to poor water management and rainfall reduction. Under current circumstances, it becomes...  相似文献   

Developing an expert group method of data handling system for predicting the geometry of a stable channel with a gravel bed   总被引：2，自引：0，他引：2       下载免费PDF全文

Azadeh Gholami  Hossein Bonakdari  Isa Ebtehaj  Saba Shaghaghi  Fatemeh Khoshbin 《地球表面变化过程与地形》2017,42(10):1460-1471

Predicting the geometry of channels and alluvial rivers is of primary importance in river engineering science. Appropriately designing channels and predicting stable river cross‐sections can decrease costs and prevent the destruction of installations and agricultural land by rivers. Consequently, researchers have applied different empirical and regression methods to achieve relations for predicting stable channel and river geometry. In this study, Group Method of Data Handling ]GMDH) models are used to predict three geometric variables of stable channels, namely width (w), depth (h) and slope (s). The effect of different input parameters, such discharge (Q), median grain size (d₅₀) and the Shields parameter (τ^*) on the GMDH models is assessed with regard to predicting stable channel geometry. The results indicate that the GMDH model with mean absolute percentage error (MAPE) of 5.53%, 4.05% and 4.89% for channel width, depth and slope prediction respectively, exhibits good accuracy. Moreover, a comparison of the GMDH models with previous theoretical equations (based on regression analysis) indicates the superiority of GMDH model performance, with error reductions of one‐fifth, one‐eighth and one‐sixth compared with the regression equations for channel width, depth and slope prediction, respectively. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

GIS-Based Groundwater Potential Mapping in Khorramabad in Lorestan,Iran, using Frequency Ratio (FR) and Weights of Evidence (WoE) Models     

Fatemeh Falah  Hossein Zeinivand 《Water Resources》2019,46(5):679-692

Water Resources - In this study groundwater potential map of Khorramabad in Lorestan Province, Iran was produced using two different methods; Frequency Ratio (FR) and Weights of Evidence (WoE)...  相似文献   

Assessing the performance of decision tree and neural network models in mapping soil properties     

Fatemeh HATEFFARD  Payam DOLATI  Ahmad HEIDARI  Ali Asghar ZOLFAGHARI 《山地科学学报》2019,(8)

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Time trend analysis of some agroclimatic variables during the last half century over Iran     

Bannayan  Mohammad  Asadi  Sara  Nouri  Milad  Yaghoubi  Fatemeh 《Theoretical and Applied Climatology》2020,140(3):839-857

Theoretical and Applied Climatology - We assessed the trends of precipitation, maximum and minimum temperature (Tmax and Tmin), diurnal temperature range (DTR), water requirement of autumn-planted...  相似文献   

Calcareous nannofossils from chalky limestone of upper Abderaz Formation and lower part of Abtalkh Formation in the Kopet-Dogh range NE Iran     

Fatemeh Hadavi  Marziyeh Notghi Moghaddam 《Arabian Journal of Geosciences》2011,4(7-8):1041-1049

For the first time, the calcareous nannofossils of the chalky limestone of upper Abderaz Formation and lower part of Abtalkh Formation have been studied. In this study, 83 nannoplanktonic species of 45 genera were identified and presented. A biostratigraphic study of calcareous nannofossils from this section has allowed the recognition of five calcareous nannofossil biozones of Sissingh (Geol Mijnbouw 56:37–65, 1977) CC17–CC21. On the obtained calcareous nannofossils, the age of this section is Late Santonian/Early Campanian–Early Late Campanian.  相似文献   

Cosmological dynamics of a quintom field on the warped DGP brane     

Kourosh Nozari  Kosar Asadi  Fatemeh Rajabi 《Astrophysics and Space Science》2014,349(1):549-559

As a generalization of the Brans-Dicke type scalar-tensor gravity in a braneworld context, we study cosmological phase space of a braneworld model with induced gravity in the presence of a scalar field on the brane. We consider a quintom field minimally or non-minimally coupled to induced gravity on the warped DGP brane and we present a detailed analysis of the critical points, their stability and late-time cosmological viability of the solutions within a phase space approach. In particular, de Sitter solutions, different from the famous self-accelerated branch of the DGP model are found and the phase-space analysis for checking their attractor properties is performed. We analyze also the possibility of crossing of the phantom divide by the effective equation of state parameter of the model. We also focus on the classical stability of the solutions in w–w′ phase plane.  相似文献   

Spectroscopy of Rindler modified Schwarzschild black hole     

Izzet Sakalli  Seyedeh Fatemeh Mirekhtiary 《Astrophysics and Space Science》2014,350(2):727-731

We study quasinormal modes (QNMs) of uncharged Grumiller black hole (GBH). This massive BH has a Rindler acceleration a, and hence it is also called Rindler modified Schwarzschild BH. After reducing the radial equation of the massless Klein-Gordon equation to the Zerilli equation, we compute the complex frequencies of the QNMs of the GBH. To this end, an approximation method which considers small perturbations around its horizon is used. Considering the highly damped QNMs in the process proposed by Maggiore, the quantum entropy and area spectra of these BHs are found. Although the QNM frequencies are tuned by the Rindler term, we show in detail that the spacing does not depend on it. Here, the dimensionless constant ? of the area spectrum is found to be double of its Schwarzschild value. The latter result is also discussed.  相似文献   

The daily travel of villagers to the city in a case study of Northern Iran     

Ahmadi Nejad Masouleh Fatemeh 《GeoJournal》2005,64(3):153-162

Rural urban migration can often result in decreased agricultural output in countries with scarce land resources. It also can hasten the socio-economic problems associated with the overcrowded cities of the developing world. As only 10% of Iran is arable it is particularly vulnerable to threats to food security and self-sufficiency. This paper examines the daily flow of villagers to a major city near the vital staple crop producing rural district of Lakan, where out-migration is already occurring. Although most discussions of daily travel to cities is typically relegated to commuting, this paper aims to analyze travel for the purpose of access to a variety of facilities and services that villages in the rural district of Lakan lack including secondary schools, post offices, banks, and even telephones and newspaper stands. The paper emphasizes that daily journeys make permanent moves to the city more likely because of the major inconvenience that results from the scarcity of basic facilities within Lakan villages. Travel to a distant city for staple foods at grocery stores or for access to secondary schools, for example, could intensify future out-migration because the heavy inconvenience of constant travel might eventually outweigh the benefits of maintaining residency in villages. The paper utilizes information about daily travel to Rasht to recommend various government construction projects and initiatives to improve the quality of life for villagers and avert future rural–urban migration and the reduction in staple crop production that might result.  相似文献