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Estimating oak forest parameters in the western mountains of iran using satellite-based vegetation indices

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Journal of Forestry Research 2020年第2期31卷 541-552页

作者： Adel Nouri bahman Kiani Mohammad hossein Hakimi Mohammad hossein Mokhtari Department of Forest Sciences Faculty of Natural ResourcesYazd UniversityYazdIslamic Republic of Iran Department of Desert Management Faculty of Natural ResourcesYazd UniversityYazdIslamic Republic of Iran

Remote sensing is an important tool for studying and modeling forest *** indices obtained from Landsat-8 remotely sensed data were used to estimate the forest parameters in the western mountains of *** sample points were selected on the map of bayangan County,Kermanshah province,*** each point,a cluster of five rectangular plots of 8100 m2 and 200 m apart was *** clusters were primarily sampled to determine the variance of the forest *** coefficient of variation was used as a criterion for sample *** density,canopy cover and basal area per hectare were calculated for each *** indices were extracted fromthe Landsat-8 images for each *** linear and nonlinear regressions were conducted to develop the *** models were validated using an independent data *** of model parameters was statistically *** results showed that Normalized difference vegetation index(NDVI)and Transformed normalized difference vegetation index(TNDVI)followed by Simple ratio vegetation index(SRVI)were the best predictors,explaining up to 91%of the variations with high *** NDVI,Soil adjusted vegetation index 2(SAVI2)and SRVI,the cubic model was more appropriate than the linear model for predicting the forest *** this model,the R-square value increased while NRMSE decreased *** Infrared percentage vegetation index(IPVI),the quadratic model was better,but,for other vegetation indices,nonlinear models were not superior to linear ***,it can be concluded that Landsat-8 imagery is suitable for predicting forest parameters in the oak forests of western *** course,large plots must be selected,and pre-classification is necessary to gain accurate and precise estimations.

关键词： basal area Canopy cover Density Landsat-8 Modeling

Corrosion resistance of aluminum alloy AA7022 wire fabricated by friction stir extrusion

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Transactions of Nonferrous Metals Society of China 2019年第8期29卷 1601-1609页

作者： Kamin TAHMASBI Masoud MAHMOODI hossein TAVAKOLI Department of Mechanical Engineering Semnan University Semnan *** Iran Faculty of Materials & Metallurgical Engineering Semnan University Semnan *** Iran

Friction stir extrusion(FSE)is known as an innovative manufacturing technology that makes it possible to directly produce wire via consolidation and extrusion of metal chips or solid *** this study,wire samples were produced using aluminum alloy AA7022 machining chips by the use of the *** this end,the microstructures and mechanical properties of the base material(BM)and the extruded samples were *** corrosion resistance of the given samples was also determined using potentiodynamic polarization *** results showed that the samples manufactured at higher rotational speeds possessed good surface quality,the process temperature and the grain size similarly increased following the rise in rotational speed,and the mechanical properties consequently *** the FSE led to crystallite refinement,increase in volume fraction of grain boundaries,as well as re-distribution of precipitates affecting corrosion ***,the findings of the corrosion tests revealed that the produced samples by the FSE had adequate corrosion resistance and the growth in die rotation rate augmented current density and subsequently reduced corrosion resistance.

关键词： friction stir extrusion aluminum alloy wire grain size hardness corrosion resistance

Plant diversity of Hyrcanian relict forests:An annotated checklist,chorology and threat categories of endemic and near endemic vascular plant species

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Plant Diversity 2022年第1期44卷 39-69页

作者： Atefeh Ghorbanalizadeh hossein Akhani Halophytes and C4 Plants Research Laboratory Department of Plant SciencesSchool of BiologyCollege of SciencesUniversity of TehranP.O.Box 14155-6455TehranIran

In this paper a critical annotated checklist of 256 endemic and near endemic species belonging to 152 genera and 50 families of flowering plants known from Hyrcanian relict forests is *** maps of taxa,elevational range,number of known records,chorotypes,life forms,IUCN threat categories and habitat types are also *** chorotypes are categorized into eight main patterns:1)the Omni-Hyrcanian pattern(OH),2)West Hyrcanian pattern(WH),3)Manjil-Rudbar pattern(MR),4)Central Hyrcanian pattern(CH),5)Central and East Hyrcanian pattern(CEH),6)East Hyrcanian pattern(EH),7)Alborz-Hyrcanian pattern(AH),and 8)Euxino-Hyrcanian pattern(XH).The richness and distribution maps were generated based on 5408 records gained from herbarium specimens and literature *** life form spectra show that the majority of taxa(54.7%)belong to hemicryptophytes,followed by the tuberous,bulbous and parasitic geophytes with 45 species(17.6%)and phanerophytes with 28 taxa(10.9%).The conservation status of species according to IUCN criteria indicates that 30 taxa are Critically Endangered,52 taxa Endangered,30 taxa Vulnerable,25 taxa Near Threatened and 81 taxa are of Least *** present data were not sufficient to evaluate 38 taxa that are categorized here as Data *** new combination of Leutea translucens(=Peucedanum translucens)is validated with inclusion of Peucedanum hyrcanicum as its *** disjunct occurrence of the Caucasian species Gentiana grossheimii is reported from the eastern parts of the Hyrcanian forests in iran for the first *** conclude that(i)the Hyrcanian forests and associated habitats in the northern slopes of the Alborz Mountains harbour tremendous floristic diversity of high conservation priority,and(ii)the Hyrcanian forest zone is an important and unique center of endemism within the Euro-Siberian region that should be considered a floristic province with a large number of relict species.

关键词： Biodiversity Distribution pattern Endemic plant Hyrcanian forests IUCN category

A functorial approach to categorical resolutions

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Science China Mathematics 2020年第10期63卷 2005-2016页

作者： Rasool Hafezi Mohammad hossein Keshavarz School of Mathematics Institute for Research in Fundamental Sciences(IPM)Tehran 19395-5746Iran

Using a relative version of Auslander’s formula,we give a functorial approach to show that the bounded derived category of every Artin algebra admits a categorical ***,in particular,implies that the bounded derived categories of Artin algebras of finite global dimension determine bounded derived categories of all Artin ***,this paper can be considered as a typical application of functor categories,introduced in representation theory by Auslander(1971),to categorical resolutions.

关键词： categorical resolutions Artin algebras Auslander’s formula

Transferring information through a mixed-five-spin chain channel

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Chinese Physics B 2016年第8期25卷 53-58页

作者： Hamid Arian Zad hossein Movahhedian Department of Physics Shahrood University of Technology

We initially introduce one-dimensional mixed-five-spin chain with Ising-XY model which includes mixture of spins-1/2 and spins-1. Here, it is considered that nearest spins（1, 1/2） have Ising-type interaction and nearest spins（1/2, 1/2）have both XY-type and Dzyaloshinskii–Moriya（DM） interactions together. Nearest spins（1, 1） have X X Heisenberg interaction. This system is in the vicinity of an external homogeneous magnetic field B in thermal equilibrium state. We promote the quantum information transmitting protocol verified for a normal spin chain with simple model（refer to Rossini D, Giovannetti V and Fazio R 2007 Int. J. Quantum Infor. 5 439）（widely in reference： Giovannetti V and Fazio R 2005 Phys. Rev. A 71 032314） by means of considering the suggested mixed-five-spin chain as a quantum communication channel for transmitting both qubits and qutrits ideally. Hence, we investigate some useful quantities such as quantum capacity and quantum information transmission rate for the system. Finally, we conclude that, when the DM interaction between spins（1/2, 1/2） increases the system is a more ideal channel for transmitting information.

关键词： Dzyaloshinskii-Moriya interaction XX Heisenberg interaction communication channel transmission rate

Reduction of the wind erosion potential in dried-up lakebeds using artificial biocrusts

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Frontiers of Earth Science 2022年第4期16卷 865-875页

作者： hossein KHEirFAM Maryam ROOHI Department of Range and Watershed Management Faculty of Natural ResourcesUrmia UniversityUrmia ***Iran Department of Environmental Sciences Urmia Lake Research InstituteUrmia UniversityUrmia ***Iran Microbiology Laboratory Expert Artemia&Aquaculture Research InstituteUrmia UniversityUrmia ***Iran

The artificial creation of biocrusts can be a rapid and pervasive solution to reduce wind erosion potential(WEP)in dried-up lakes(e.g.,Lake Urmia).So,in this study,we created a biocrust by the inoculation of bacteria and cyanobacteria on trays filled by soils collected from the dried-up bed of Lake Urmia.iran,to reduce WEP in laboratory *** used the wind erodible fraction of soil(EF)and soil crust factor(SCF)equations to calculate the WEP of the treated *** and SCF were decreased(pbacteria and cyanobacteria by 5.6%and 10.57%,respectively,as compared to the control;also,the"cyanobacteria alone"inoculation decreased EF by 3.9%.Our results showed that the artificial biocrusts created by soil inoculation,especially with the co-using of bacteria and cyanobacteria,significantly reduced the WEP of a newly dried-up ***,we found that inoculation decreased the WEP of the study soil by increasing the soil organic matter content from 3.7 to 5 *** to scanning electron microscopy images,the inoculated microorganisms,especially cyanobacteria,improved soil aggregation by their exopolysaccharides and filaments;thus,they can be used with other factors to estimate the soil erodibility in well-developed *** inoculation technique could be considered as a rapid strategy in stabilizing lakebeds against wind ***,it should be confirmed after additional experiments using wind tunnels under natural conditions.

关键词： biological soil crust dried-up lakes dust storms flowing-sands soil cyanobacteria

Logarithmic Gradient Transformation and Chaos Expansion of Ito Processes

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Communications in Mathematics and Statistics 2022年第2期10卷 215-231页

作者： hossein Gorji Computational Mathematics and Simulation Science Ecole polytechnique federal de Lausanne1015 LausanneSwitzerland

Since the seminal work of Wiener(Am J Math 60:897-936,1938),chaos expansion has evolved to a powerful methodology for studying a broad range of stochastic differential *** its complexity for systems subject to the white noise remains *** issue appears due to the fact that the random increments generated by the Brownian motion result in a growing set of random variables with respect to which the process could be *** order to cope with this high dimensionality,we present a novel transformation of stochastic processes driven by the white *** particular,we show that under suitable assumptions,the diffusion arising from white noise can be cast into a logarithmic gradient induced by the measure of the *** this transformation,the resulting equation describes a stochastic process whose randomness depends only on the initial ***,the stochasticity of the transformed system lives in the initial condition and it can be treated conveniently with chaos expansion tools.

关键词： Ito process Chaos expansion Fokker-Planck equation

Energy-based numerical models for assessment of soil liquefaction

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Geoscience Frontiers 2012年第4期3卷 541-555页

作者： a.ir hossein Alavi a.ir hossein Gandomi School of Civil Engineering lran University of Science and TechnologyTehranIran College of Civil Engineering Tafresh UniversityTafreshlran

This study presents promising variants of genetic programming （GP）, namely linear genetic programming （LGP） and multi expression programming （MEP） to evaluate the liquefaction resistance of san- dy soils. Generalized LGP and MEP-based relationships were developed between the strain energy density required to trigger liquefaction （capacity energy） and the factors affecting the liquefaction characteristics of sands. The correlations were established based on well established and widely dispersed experimental results obtained from the literature. To verify the applicability of the derived models, they were employed to estimate the capacity energy values of parts of the test results that were not included in the analysis. The external validation of the models was verified using statistical criteria recommended by researchers. Sensitivity and parametric analyses were performed for further verification of the correlations. The results indicate that the proposed correlations are effectively capable of capturing the liquefaction resistance of a number of sandy soils. The developed correlations provide a significantly better prediction performance than the models found in the literature. Furthermore, the best LGP and MEP models perform superior than the optimal traditional GP model. The verification phases confirm the efficiency of the derived correlations for their general application to the assessment of the strain energy at the onset of liquefaction.

关键词： Soil liquefaction Capacity energy Linear genetic programming Multi expression programming Sand Formulation

Effect of rare earth elements addition on thermal fatigue behaviors of AZ91 magnesium alloy

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Journal of Rare Earths 2009年第2期27卷 255-258页

作者： hossein bayani Ehsan Saebnoori Department of Materials Science and Engineering Sharif University of TechnologyP.O. Box:11365-9466Tehran-Iran Department of Materials Science and Engineering Tarbiat Modares UniversityP.O.Box:14115-143Tehran-Iran

Influences of rare earth （RE） elements addition on thermal fatigue behaviors of AZ91 alloy were studied. Repeated heating and cooling cycles were applied on the samples at 170 and 210℃ to develop thermal fatigue cracks. Crack growth mechanisms and microstructural influences were investigated by optical and scanning electron microscopy （SEM） as well as energy dispersive X-ray spectroscopy （EDS）. Thermal fatigue behaviors were observed to improve successively by addition of the RE up to 2wt.%. This improvement was attributed to the consummation of aluminum in melt by precipitation of the needle shaped AII1RE3 phases. This process was attributed to the reduction of MglTAl12 phase volume fraction and consequent decrease of the brittle Mg/MglTAl12 interface which was the main reason for weak thermal properties of the alloy at rather high temperatures. Further additions of RE, however, reduced the thermal shock resistance of the samples by increasing the mean length of the brittle needle shaped phases.

关键词： AZ91 alloy rare earth elements thermal fatigue thermal shock resistance