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Homogeneity analysis of streamflow records in arid and semi-arid regions of northwestern Iran

Journal of Arid Land 2018年第4期10卷 493-506页

作者： Majid KAZEMZADEH arash malekian University of Tehran Karaj 31587-77871Iran

Homogeneity analysis of the streamflow time series is essential to hydrological modeling, water resources management and climate change studies. In this study, five absolute homogeneity tests and one clustering approach were used to determine the homogeneity status of the streamflow time series （over the period 1960-2010） in 14 hydrometric stations of three important basins （i.e., Aras River Basin, Urmia Lake Basin and Sefid-Roud Basin） in northwestern Iran. Results of the Buishand range test, yon Neumann ratio test, cumulative deviation test, standard normal homogeneity test and Pettitt test for monthly streamflow time series detected that about 42.26%, 38.09%, 33.33%, 39.28% and 68.45% of the streamflow time series were inhomogeneous at the 0.01 significance level, respectively. Streamflow time series of the stations located in the eastern parts of the study area or within the Urmia Lake Basin were mostly homogeneous. In contrast, streamflow time series in the stations of the Aras River Basin and Sefied-Roud Basin showed inhomogeneity at annual scales. Based on the overall classification for the monthly and annual streamflow series, we determined that about 45.60%, 11.53% and 42.85% of the time series were categorized into the ＇useful＇, ＇doubtful＇ and ＇suspect＇ classes according to the five absolute homogeneity tests. We also found the homogeneity patterns of the streamflow time series by using the clustering approach. The results suggested the effectiveness of the clustering approach for homogeneity analysis of the streamflow time series in addition to the absolute homogeneity tests. Moreover, results of the absolute homogeneity tests and clustering approach indicated obvious decreasing change points of the streamflow time series in the 1990s over the three basins, which were mostly related to the hydrological droughts.

关键词： streamflow time series homogeneity test clustering analysis inhomogeneity Urmia Lake northwestern Iran

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Precipitation forecasting by large-scale climate indices and machine learning techniques

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Journal of Arid Land 2020年第5期12卷 854-864页

作者： Mehdi GHOLAMI ROSTAM Seyyed Javad SADATINEJAD arash malekian University of Tehran Tehran ***Iran

Global warming is one of the most complicated challenges of our time causing considerable tension on our societies and on the *** impacts of global warming are felt unprecedentedly in a wide variety of ways from shifting weather patterns that threatens food production,to rising sea levels that deteriorates the risk of catastrophic *** all aspects related to global warming,there is a growing concern on water resource *** field is targeted at preventing future water crisis threatening human *** very first stage in such management is to recognize the prospective climate parameters influencing the future water resource *** prediction models,methods and tools,in this case,have been developed and applied so *** line with trend,the current study intends to compare three optimization algorithms on the platform of a multilayer perceptron(MLP)network to explore any meaningful connection between large-scale climate indices(LSCIs)and precipitation in the capital of Iran,a country which is located in an arid and semi-arid region and suffers from severe water scarcity caused by mismanagement over years and intensified by global *** situation has propelled a great deal of population to immigrate towards more developed cities within the country especially towards ***,the current and future environmental conditions of this city especially its water supply conditions are of great *** tackle this complication an outlook for the future precipitation should be provided and appropriate forecasting trajectories compatible with this region's characteristics should be *** this end,the present study investigates three training methods namely backpropagation(BP),genetic algorithms(GAs),and particle swarm optimization(PSO)algorithms on a MLP *** frameworks distinguished by their input compositions are denoted in this study:Concurrent Model Framework(CMF)and Integrated Model Framework(

关键词： backpropagation genetic algorithms machine learning multilayer perceptron particle swarm optimization Taylor diagram

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Watershed classification by remote sensing indices： A fuzzy c-means clustering approach

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Journal of Mountain Science 2017年第10期14卷 2053-2063页

作者： Bahram CHOUBIN Karim SOLAIMANI Mahmoud HABIBNEJAD ROSHAN arash malekian Department of Watershed Management Sari University of Agricultural Sciences and Natural Resources P.O. Box 737 Sari Iran Department of Reclamation of Arid and Mountainous Regions University of Tehran Karaj 31585-3314 Iran

Determining the relatively similar hydrological properties of the watersheds is very crucial in order to readily classify them for management practices such as flood and soil erosion control. This study aimed to identify homogeneous hydrological watersheds using remote sensing data in western Iran. To achieve this goal, remote sensing indices including SAVI, LAI, NDMI, NDVI and snow cover, were extracted from MODIS data over the period 2000 to 2015. Then, a fuzzy method was used to clustering the watersheds based on the extracted indices. A fuzzy c-mean(FCM) algorithm enabled to classify 38 watersheds in three homogeneous *** optimal number of clusters was determined through evaluation of partition coefficient, partition entropy function and trial and error. The results indicated three homogeneous regions identified by the fuzzy c-mean clustering and remote sensing product which are consistent with the variations of topography and climate of the study area. Inherently,the grouped watersheds have similar hydrological properties and are likely to need similar management considerations and measures.

关键词： Karkheh watershed Fuzzy c-means clustering Watershed classification Homogeneous sub-watersheds

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Drought Forecasting in a Semi-arid Watershed Using Climate Signals:a Neuro-fuzzy Modeling Approach

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Journal of Mountain Science 2014年第6期11卷 1593-1605页

作者： Bahram CHOUBIN Shahram KHALIGHI-SIGAROODI arash malekian Sajjad AHMAD Pedram ATTAROD Department of Watershed Management Sari University of Agriculture Sciences and Natural ResourcesSari 48181-68984Iran University of Tehran Faculty of Natural ResourcesKaraj 31585-3314 Iran Department of Civil and Environmental Engineering University of NevadaLas Vegas NV 89154-4015 USA

Large-scale annual climate indices were used to forecast annual drought conditions in the Maharlu-Bakhtegan watershed,located in Iran,using a neuro-fuzzy *** Standardized Precipitation Index(SPI) was used as a proxy for drought *** the 45 climate indices considered,eight identified as most relevant were the Atlantic Multidecadal Oscillation(AMO),Atlantic Meridional Mode(AMM),the Bivariate ENSO Time series(BEST),the East Central Tropical Pacific Surface Temperature(NINO 3.4),the Central Tropical Pacific Surface Temperature(NINO 4),the North Tropical Atlantic Index(NTA),the Southern Oscillation Index(SOI),and the Tropical Northern Atlantic Index(TNA).These indices accounted for 81% of the variance in the Principal Components Analysis(PCA) *** Atlantic surface temperature(SST:Atlantic) had an inverse relationship with SPI,and the AMM index had the highest *** forecasts of neuro-fuzzy model demonstrate better prediction at a two-year lag compared to a stepwise regression model.

关键词： Annual Rainfall Large-scale Climate Signals Neuro-Fuzzy Cross-Correlation Principal Components Analysis Drought

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Economic valuation of water storage function of forest ecosystems (case study: Zagros Forests, Iran)

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Journal of Forestry Research 2010年第3期21卷 293-300,396,397页

作者： Zahra Mashayekhi Mostafa Panahi Mahmoud Karami Shahram Khalighi arash malekian Natural Resources Faculty University of Tehran Islamic Azad University

Forest ecosystem services contribute to human welfare, both directly and indirectly. Here the economic value of water conservation by Bazoft basin located in Zagros forests in western Iran was estimated, using simulation models and Geographic Information System （GIS） as a tool for analyzing the effects of ecological factors on ecosystem services. Rainfall-runoff simulation was carried out by using Curve Number （CN） method in HEC-HMS model. The model requires the inputs of land cover, soil and short term rainfall and discharge data. The efficiency of simu-lated model was revised using observed data and doing calibration stages. The role of forest on water retention and surface runoff reduction by devising four hypothetical scenarios and then the effects of land use changes associated with these scenarios on rainfall-runoff behavior of the region were determined. The results show that under the case of scenario one which assumes that the entire of basin area is covered by forests, total outflow would be in the minimum amount and rainfall initial loss will increase. Forest hydrological services related to water retention was economically assessed using Replacement Cost Method. Valuation results show that each hectare of Bazoft forests can store 84.8 m3 water with 0.5 US$/m3 annual value. So the water retention value of each hectare of these forests will be 43US$. This could have positive economic consequences for the region and would help decision-makers in selecting appropriate and economically feasible development strategies.

关键词： Bazoft River basin curve number economic valuation replacement cost runoff

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Recent advances in flat sheet mixed matrix membrane modified by Mg-based layered double hydroxides(LDHs)for salt and organic compound separations

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Journal of Magnesium and Alloys 2024年第6期12卷 2182-2200页

作者： Payam Veisi arash Fattah-alhosseini Mosab Kaseem Department of Materials Engineering Faculty of EngineeringBu-Ali Sina UniversityHamedanIran Corrosion and Electrochemistry Laboratory Department of Nanotechnology and Advanced Materials EngineeringSejong UniversitySeoul 05006Republic of Korea

Magnesium(Mg)is a widely used and attractive metal,known for its unique physical and chemical properties,and it has been employed in the manufacture of many practical *** Double Hydroxides(LDHs),particularly Mg-based LDHs,rank among the most prevalent two-dimensional materials utilized in separation processes,which include adsorption,extraction,and membrane *** high popularity of Mg-based LDHs in separation applications can be attributed to their properties,such as excellent hydrophilicity,high surface area,ion exchangeability,and adjustable interlayer ***,polymer membranes play a pivotal role in semi-industrial and industrial separation ***,the development of polymer membranes and the mitigation of their limitations have emerged as compelling topics for *** methods exist to enhance the separation performance and anti-fouling properties of polymer *** these,incorporating additives into the membrane polymer matrix stands out as a cost-effective,straightforward,readily available,and efficient *** use of Mg-based LDHs,either in combination with other materials or as a standalone additive in the polymer membrane matrix,represents a promising strategy to bolster the separation and anti-fouling efficacy of flat sheet mixed matrix polymer *** review highlights Mg-based LDHs as high-potential additives designed to refine flat sheet mixed matrix polymer membranes for applications in wastewater treatment and brackish water desalination.

关键词： Mg-based layered double hydroxides(LDHs) Mixed matrix membrane Polymeric membrane Water and wastewater treatment Brackishwater desalination

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Commentary on"Speed and surface steepness affect internal tibial loading during running"

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Journal of Sport and Health Science 2024年第1期13卷 125-126页

作者： Michael Baggaley arash Khassetarash Faculty of Kinesiology University of CalgaryCalgaryAB T2N 1N4Canada McCaig Institute for Bone and Joint Health University of CalgaryCalgaryAB T2N 4Z6Canada

It is a pleasure to write a commentary on the work of *** Rice and colleagues,l who have advanced our understanding of how the mechanical loading environment of the tibia changes as a function of running grade and *** is important that we understand how the tibia is loaded during conditions that an individual is likely to encounter when running as it is these internal loads which we believe are responsible for the development of bone-stress injuries.

关键词： loading injuries likely

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In search of optimal building behavior models for model predictive control in the context of flexibility

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Building Simulation 2024年第1期17卷 71-91页

作者： arash Erfani Tohid Jafarinejad Staf Roels Dirk Saelens KU Leuven Department of Civil EngineeringBuilding Physics and Sustainable Design SectionKasteelpark Arenberg 40 Bus 24473001 HeverleeBelgium EnergyVille Thor Park 8310Genk 3600Belgium

Model predictive control(MPC)is an advanced control *** has been deployed to harness the energy flexibility of a *** requires a dynamic model of the building to achieve such an ***,developing a suitable predictive model is the main challenge in MPC implementation forflexibility *** studyfocuses on the application of key performance indicators(KPls)to evaluate the suitability of MPC models via feature *** this end,multiple models were developed for two houses.A feature selection method was developed to select an appropriate feature space to train the *** predictive models were then quantified based on one-step ahead prediction error(OSPE),a standard KPI used in multiple studies,and a less-often KPl:multi-step ahead prediction error(MSPE).An MPC workflow was designed where different models can serve as the predictive *** showed that MSPE better demonstrates the performance of predictive models used for flexibility *** revealed that up to 57% of the flexibility potential and 48% of energy use reduction are not exploited if MSPE is not minimized while developing a predictive model.

关键词： building flexibility model predictive control for building building behaviour identification smart home

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Surface growth of novel MOFs on AZ31 Mg alloy coated via plasma electrolytic oxidation for enhanced corrosion protection and photocatalytic performance

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Journal of Magnesium and Alloys 2024年第6期12卷 2413-2432页

作者： Ananda Repycha Safira arash Fattah-alhosseini Mosab Kaseem Corrosion and Electrochemistry Laboratory Department of Nanotechnology and Advanced Materials EngineeringSejong UniversitySeoul 05006Republic of Korea Department of Materials Engineering Faculty of EngineeringBu-Ali Sina UniversityHamedanIran

In the pursuit of multifunctional coatings,the controlled growth of materials on stationary platforms holds paramount importance for achieving superior corrosion protection and optimal photocatalytic *** study introduces a cutting-edge approach,intertwining bifunctional metal-organic frameworks(MOFs)seamlessly into defective MgO layers produced by the anodic oxidation of AZ31 *** metallic oxides of Zn,Sn,and V take center stage as metallic sources for MOF formation,complemented by the organic prowess of L-Tryptophan as anα-amino acid *** the electronic structure of metallic oxides reacting with tryptophan molecules,controlled morphologies with distinct characteristics are induced on the defective surface of the MgO layer,enabling the precise modulation of surface *** hybrid composite demonstrates an adaptive microstructure in diverse aqueous environments,offering dual functionality with electrochemical stability and visible light photocatalytic activity for crystal violet *** the samples,the SnOF complex exhibited remarkable electrochemical stability with a low corrosion current density of 7.50×10^(−10)A·cm^(−2),along with a 94.56%degradation efficiency after 90 min under visible light *** VOF complex,under similar visible light conditions,demonstrated exceptional performance with a higher degradation efficiency of 97.79%and excellent electrochemical stability characterized by a corrosion current density of 3.26×10^(−9)A·cm^(−2).Additionally,Density Functional Theory(DFT)computations shed light on the basic bonding patterns between MOFs and inorganic components,providing electronic understanding of their electrochemical and photocatalytic activities.

关键词： Electrochemical stability Defective layer Metal-organic framework Photocatalytic activity DFT

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Novel interface engineering of LDH-based materials on Mg alloy for efficient photocatalytic systems considering the geometrical linearity of condensed phosphates

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Journal of Magnesium and Alloys 2024年第1期12卷 267-280页

作者： Mosab Kaseem Ananda Repycha Safira arash Fattah-alhosseini Department of Nanotechnology and Advanced Materials Engineering Corrosion and Electrochemistry LaboratorySejong UniversitySeoul 05006Republic of Korea Department of Materials Engineering Bu-Ali Sina UniversityHamedan 65178-38695Iran

This study presents a facile and rapid method for synthesizing novel Layered Double Hydroxide(LDH)nanoflakes,exploring their application as a photocatalyst,and investigating the influence of condensed phosphates'geometric linearity on their photocatalytic ***,the Mg O film,obtained by plasma electrolysis of AZ31 Mg alloys,was modified by growing an LDH film,which was further functionalized using cyclic sodium hexametaphosphate(CP)and linear sodium tripolyphosphate(LP).CP acted as an enhancer for flake spacing within the LDH structure,while LP changed flake dispersion and ***,CP@LDH demonstrated exceptional efficiency in heterogeneous photocatalysis,effectively degrading organic dyes like Methylene blue(MB),Congo red(CR),and Methyl orange(MO).The unique cyclic structure of CP likely enhances surface reactions and improves the catalyst's interaction with dye ***,the condensed phosphate structure contributes to a higher surface area and reactivity in CP@LDH,leading to its superior photocatalytic performance compared to LP@***,LP@LDH demonstrated notable degradation efficiencies of 93.02%,92.89%,and 88.81%for MB,MO,and CR respectively,over a 40 min *** highest degradation efficiencies were observed in the case of the CP@LDH sample,reporting 99.99%for MB,98.88%for CR,and 99.70%for *** underscores the potential of CP@LDH as a highly effective photocatalyst for organic dye degradation,offering promising prospects for environmental remediation and water detoxification applications.

关键词： Plasma electrolysis Layered Double Hydroxide Condensed phosphates Adsorption capacity Photocatalytic efficiency

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