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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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Effects of Yttrium Addition on Microstructure, Hardness and Resistance to Wear and Corrosive Wear of TiNi Alloy

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Journal of Materials Science & Technology 2011年第9期27卷 851-855页

作者： Hojat Ahmadi Meisam nouri Faculty of Biosystems Engineering University of Tehran Department of Materials Engineering Tarbiat Modares University

TiNi alloy has a high resistance to wear and could be an excellent candidate for various tribological applications. In this paper, it was demonstrated that by addition of yttrium, hardness properties and resistance to wear and corrosive wear of TiNi alloy were improved. New yttrium rich regions were formed in microstructure of TiNi alloy. The improved properties of this alloy by the yttrium addition could be attributed to the formation of these regions. The results showed that there was an optimum content for addition of yttrium between 2% and 5% （in wt%）, and above this content the improvement in properties of TiNi became minor.

关键词： Yttrium TiNi Mechanical behaviour Wear Corrosive wear Microstructure

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ELECTROSPINNING OF CYCLODEXTRIN FUNCTIONALIZED CHITOSAN/PVA NANOFIBERS AS A DRUG DELIVERY SYSTEM

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Chinese Journal of Polymer Science 2013年第10期31卷 1343-1351页

作者： Maryam Bazhban Mahdi nouri Javad Mokhtari Department of Textile Engineering Faculty of Engineering University of Guilan

A new type ofnanofibrous structure from chitosan bearing carboxymethyl-β-cyclodextrin （CS-g-β-CD） as a novel drug delivery system was synthesized by grafting carboxymethyl-β-cyclodextrin （CM β-CD） onto chitosan （CS） in the presence of water soluble 1-ethyl-3-（3-dimethylaminopropyl） carbodiimide （EDC） as the condensing agent and N-hydroxysuccinimide （NHS）. Defect free mats containing CS-g-β-CD have been fabricated using electrospirming of an aqueous solution of poly（vinyl alcohol）（PVA）/CS-g-β-CD blends. The morphology and diameter of the electrospun nanofibers were examined by scanning electron microscopy （SEM）. The average fiber diameter was in the range of 130-210 run. SEM images showed that the morphology and diameter of the nanofibers were mainly affected by weight ratio of the blend at constant applied voltage. The results revealed that increasing CS-g-β-CD content in the blends decreases the average fiber diameter. It was observed that the PVA/CS-g-β-CD nanofibrous mat provided a slower release of the entrapped drug in compare to PVA/CS nanofibrous mat.

关键词： Chitosan βcyclodextrin Nanofibers Drug delivery.

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NAPHTHALIMIDE BASED DISPERSE DYES FOR NYLON 6 AND POLYESTER(PET) FIBERS:SYNTHESIS AND EVALUATION OF TECHNICAL PROPERTIES IN THE PRESENCE OF UREA

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Chinese Journal of Polymer Science 2011年第6期29卷 712-718页

作者： Javad Mokhtari Mahdi nouri Uranus Goudarzi Department of Textile Engineering Faculty of EngineeringUniversity of GuilanRashtIran

Technical properties of two naphthalimide based disperse dyes on nylon 6 and polyester fibers were investigated in the presence of urea. The two naphthalimide based disperse dyes were synthesized. The dyes were purified and then fully characterized using 1H-NMR, FTIR and melting point analysis. Dispersion of the dyes was prepared in water and applied on nylon 6 and PET fibers. The dyes offered good build-up properties on the substrates. In order to increase dye adsorption of the substrates, urea was added into the dyebath. By adding urea, the dye adsorption of polyester was increased significantly, while the increase of that of nylon 6 was not marked. The dyes showed good fastness properties on the substrates.

关键词： Naphthalimide Nylon 6 Polyester Urea Disperse dye

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Applying Sliding Mode Control to Suppress Double Frequency Voltage Ripples in Single-phase Quasi-Z-source Inverters

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CSEE Journal of Power and Energy Systems 2023年第2期9卷 671-681页

作者： Jaber Merrikhi Ahangarkolaei Mahdi Izadi Tohid nouri Department of Electrical Engineering Sari BranchIslamic Azad UniversitySariIran Department of Electrical Engineering Shahriar BranchIslamic Azad UniversityShahriarIran

The inherent double-line frequency ripple(DFR)of the single-phase quasi-Z-Source inverter(qZSI)strongly affects performance and design of the whole system,which requires hardware improvement methods such as additional semiconductor components or increasing the volume of capacitors and *** a result,hardware solutions increase the price,and the volume and also reduces reliability of the *** this paper,as a non-hardware solution,a sliding mode control(SMC)method is presented to control the voltage of the qZSI *** suppress the DFR,a second-order harmonic is injected into the capacitor reference *** and experimental results show that the introduced controller will have satisfactory results in reducing the DFR without any hardware changes in the qZSI,such as increasing the volume of the capacitor and inductor,adding a semiconductor,or increasing the frequency.A simulation model and experimental prototype are provided to demonstrate the validation of the effectiveness of the proposed controller.

关键词： Double-frequency ripple quasi-Z-source inverter sliding mode control

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DRAG REDUCTION IN A TURBULENT CHANNEL FLOW WITH HYDROPHOBIC WALL

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Journal of Hydrodynamics 2012年第3期24卷 458-466页

作者： nouri Nowrouz Mohammad SEKHAVAT Setareh MOFIDI Alireza Department of Mechanical Engineering Iran University of Science and TechnologyTehran Iran

This paper investigates a theoretical prediction of friction drag reduction in turbulent channel flow which is achieved by using superhydrophobic surfaces. The effect of the hydrophobic surface is considered to be a slip boundary condition on the wall, and this new boundary condition is added to Large Eddy Simulation （LES） equations. The predicted drag reduction at Rer= 180 is approximately 30%, which concurs with results obtained from Direct Numerical Simulation （DNS）. An important implication of the present finding is that the near-wall turbulence structures are modified with streamwise slip velocity. In addition, a noticeable effect on the turbulence structure occurs when the slin lenmh is ereater than a certain vahle

关键词： superhydrophobic surface Large Eddy Simulation (LES) drag reduction slip length turbulence structures

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Constitutive model for monotonic and cyclic responses of loosely cemented sand formations

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第4期10卷 740-752页

作者： Mojtaba Rahimi Dave Chan Alireza nouri Department of Mechanical Engineering Azad UniversityKhomeinishahr BranchIsfahanIran Department of Civil and Environmental Engineering University of AlbertaEdmontonT6G 2W2Canada China Three Gorges University YichangChina

This paper presents a model to simulate the monotonic and cyclic behaviours of weakly cemented *** elastoplastic constitutive model within the framework of bounding surface plasticity theory is adopted to predict the mechanical behaviour of soft sandstone under monotonic and cyclic loadings. In this model, the loading surface always passes through the current stress state regardless of the type of loading. Destruction of the cementation bonds by plastic deformation in the model is considered as the primary mechanism responsible for the mechanical degradation of loosely cemented sands/weak *** model cyclic response, the unloading plastic and elastic moduli are formulated based on the loading/reloading plastic and elastic moduli. The proposed model was implemented in FLAC2D and evaluated against laboratory triaxial tests under monotonic and cyclic loadings, and the model results agreed well with the experimental observations. For cyclic tests, hysteresis loops are captured with reasonable accuracy.

关键词： Cyclic loading Monotonic loading Cemented sand Plasticity Constitutive model

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U-shaped energy loss curves utilization for distributed generation optimization in distribution networks

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第11期14卷 887-898页

作者： Reza EBRAHIMI Mehdi EHSAN Hassan nouri Department of Electrical Engineering Science and Research BranchIslamic Azad University Centre of Excellence in Power System Management and Control (CEPSMC) Sharif University of Technology Department of Engineering Design and Mathematics University of the West of England (UWE Bristol)

We propose novel techniques to find the optimal location,size,and power factor of distributed generation(DG) to achieve the maximum loss reduction for distribution *** the optimal DG location and size is achieved simultaneously using the energy loss curves technique for a pre-selected power factor that gives the best DG *** on the network's total load demand,four DG sizes are *** are used to form energy loss curves for each bus and then for determining the optimal DG *** study shows that by defining the energy loss minimization as the objective function,the time-varying load demand significantly affects the sizing of DG resources in distribution networks,whereas consideration of power loss as the objective function leads to inconsistent interpretation of loss reduction and other *** devised technique was tested on two test distribution systems of varying size and complexity and validated by comparison with the exhaustive iterative method(EIM) and recently published *** showed that the proposed technique can provide an optimal solution with less computation.

关键词： Distributed generation(DG) Distribution networks Loss reduction DG optimization Energy loss curves

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An Alternative Approach to the Extraction of Structure Functions in Deep Inelastic e—p Scattering at 5 to 20 GeV

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Communications in Theoretical Physics 2003年第5期39卷 573-578页

作者： N.Ghahramany M.nouri DepartmentofPhysics ShirazUniversityShiraz71548Iran

Two structure functions W1(x,Q2) and W2(x,Q2) are determined by using the cross sections measured in the deep inelastic electron-proton scattering experiments at Stanford Linac in the energy range of 5 to 20 GeV. In this paper an alternative mathematical approach have been used in such determination, resulting in a larger number of points in the graphs of the structure functions.

关键词：结构函数无弹性散射横截面交错逼近粒子模型

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Analysis of shear rate effects on drag reduction in turbulent channel flow with superhydrophobic wall

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Journal of Hydrodynamics 2013年第6期25卷 944-953页

作者： nouri Nowrouz Mohammad BAKHSH Mohammad Saadat SEKHAVAT Setareh School of Mechanical Engineering Iran University of Science and Technology

We examined the shear rate effect on drag reduction of superhydrophobic surfaces with different slip lengths. For this purpose, turbulent channel flow was considered at the friction Reynolds numbers of Reτ = 180, 395, 500. By using Navier＇s slip condition it is shown that increasing shear rate leads to the greater reduction in drag force and also more reduction occurs in larger slip length. Based on the results, more than 25% drag reduction happens at a friction Reynolds number of Reτ= 500 for slip length of 1 ×10 5 m. The simulation results suggest that reduction in drag force occurs because slip condition reduces the Reynolds stresses, also weakens vorticity filed and the near-wall coherent structures, and therefore turbulence production is decreased.

关键词： superhydrophobic shear rate drag reduction coherent structures channel flow

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