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

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

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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

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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(p<0.05)through applying the co-inoculation of bacteria 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

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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

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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： Amir hossein Alavi Amir 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

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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

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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

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On the finite horizon Nash equilibrium solution in the differential game approach to formation control

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Journal of Systems Engineering and Electronics 2019年第6期30卷 1233-1242页

作者： JOND hossein Barghi NABIYEV Vasif Department of Computer Engineering Karadeniz Technical University

The solvability of the coupled Riccati differential equations appearing in the differential game approach to the formation control problem is vital to the finite horizon Nash equilibrium *** equations(if solvable)can be solved numerically by using the terminal value and the backward *** investigate the solvability and solution of these equations the formation control problem as the differential game is replaced by a discrete-time dynamic *** main contributions of this paper are as ***,the existence of Nash equilibrium controls for the discretetime formation control problem is ***,a backward iteration approximate solution to the coupled Riccati differential equations in the continuous-time differential game is *** illustrative example is given to justify the models and solution.

关键词： formation control differential game dynamic game Nash equilibrium coupled Riccati equations.

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Perfect GMR effect in gapped graphene-based ferromagnetic normal ferromagnetic junctions

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Chinese Physics B 2015年第4期24卷 405-410页

作者： hossein Karbaschi Gholam Reza Rashedi Department of Physics University of Isfahan

We investigate the quantum transport property in gapped graphene-based ferromagnetic/normal/ferromagnetic （FG/NG/FG） junctions by using the Dirac-Bogoliubov-de Gennes equation. The graphene is fabricated on SiC and BN substrates separately, so carders in FG/NG/FG structures are considered as massive relativistic particles. Transmission prob- ability, charge, and spin conductances are studied as a function of exchange energy of ferromagnets （h）, size of graphene gap, and thickness of normal graphene region （L） respectively. Using the experimental values of Fermi energy in the normal graphene part （EFN - 400 meV） and energy gap in graphene （260 meV for SiC and 50 meV for BN substrate）, it is shown that this structure can be used for both spin-up and spin-down polarized current. The latter case has different behavior of gapped FG/NG/FG from that of gapless FG/NG/FG structures. Also perfect charge giant magnetoresistance is observed in a range of E FN - mv 2 F〈h〈E FN＋mv 2 F.

关键词： graphene spin-polarized current giant magnetoresistance nanoscale structures

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Construction of a PVC based 15-crown-5 electrochemical sensor for Ag(Ⅰ) cation

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Chinese Chemical Letters 2014年第5期25卷 809-814页

作者： Fereshteh Karimian Gholam hossein Rounaghi Mohammad hossein Arbab-Zavar Department of Chemistry Faculty of SciencesFerdowsi University of Mashhad

The macrocyclic ligand,15-crown-5,was used as an ionophore for fabrication of a polyvinyl chloride（PVC） based membrane sensor for Ag（Ⅰ） *** construction of the Ag（Ⅰ） cation selective electrode the best response characteristics were obtained using the composition： 15-crown-5/PVC/o-nitrophenyloctylether（NPOE）/sodium tetraphenyl borate（NaTPB） in the percentage ratio of 5.6/30/60.5/3.9（w/w/w/w）.The electrochemical sensor shows a linear dynamic range 1.0 10 7–1.0 10 1mol/L and a Nernstian slope of 58.9 0.5 mV/decade with a detection limit of 8.09 10 8mol/L for Ag（Ⅰ） *** has a fast response time of 〈10 s and can be used for at least 8 weeks without any considerable divergences in its potential *** was successfully used as an indicator electrode in potentiometric titration of Ag（Ⅰ）cation with I and Cl anions and also for the determination of this metal cation in radiology waste water.

关键词： 15-Crown-5 Electrochemical sensor Potentiometry Ag(I)

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