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Advanced land observing satellite data to identify ground vegetation in a juniper forest,northeast Iran

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Journal of Forestry Research 2020年第2期31卷 531-539页

作者： hadi Fadaei Geography Group Amin Police-Science UniversityTehranIran

Juniperus excelsa ***,(Persian juniper),is found in northeast *** this study,the relationship between ground cover and vegetation indices have been investigated using remote sensing data for a Persian juniper *** data were analyzed based on the Advanced Visible and Near Infrared Radiometer type 2 and panchromatic data obtained by the Panchromatic Remote-sensing Instrument for Stereo Mapping sensors,both on board the advanced land observing satellite(ALOS).The ground cover was calculated using field survey data from 25 sub-sample plots and the vegetation indices were derived with 595 maximum filtering algorithm from ALOS data.R2 values were calculated for the normalized difference vegetation index(NDVI)and various soil-adjusted vegetation indices(SAVI)with soilbrightness-dependent correction factors equal to 1 and 0.5,a modified SAVI(MSAVI)and an optimized SAVI(OSAVI).R2 values for the NDVI,MSAVI,OSAVI,SAVI(1),and SAVI(0.5)were 0.566,0.545,0.619,0.603,and 0.607,*** ratio vegetation index for arid and semi-arid regions based on spectral wavelengths of ALOS data with an R2 value 0.633 was *** of the current study will be useful for forest inventories in arid and semi-arid regions in addition to assisting decisionmaking for natural resource managers.

关键词： Ground cover Juniperus excelsa subsp.polycarpos Vegetation indices Advanced land observing satellite(ALOS)

A Sliding Mode Controller Based on Robust Model Reference Adaptive Proportional-integral Control for Stand-alone Three-phase Inverter

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Journal of Modern Power Systems and Clean Energy 2021年第3期9卷 668-678页

作者： hadi Esmaeili Mehdi Asadi Arak University of Technology ArakIran

This paper proposes a sliding mode controller based on robust model reference adaptive proportional-integral(RMRA-PI)control for a stand-alone voltage source inverter(SA-VSI).The proposed controller has two control loops where the coefficients of PI controller are regulated by the adaptive sliding *** method is used to regulate the output voltage of the inverter under different load conditions and uncertainty,and adapts the output to the reference model to reduce the total harmonic distortion(THD).In this paper,the stability of the proposed controller is proven by using Lyapunov's theory and Barbalet’s *** proposed controller performs well in voltage regulation such as low THD under sudden load change and ***,the results of the proposed controller are compared with PI controller to show the effectiveness of the presented control system.

关键词： Robust model reference adaptive proportional-integral(RMRA-PI)control stand-alone inverter three-phase inverter voltage control Lyapunov's theory

Uncertainty propagation in dynamics of composite plates: A semi-analytical non-sampling-based approach

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Frontiers of Structural and Civil Engineering 2020年第6期14卷 1359-1371页

作者： Mahdi FAKOOR hadi PARVIZ Faculty of New Sciences and Technologies University o f TehranTehran 14395-1561Iran

In this study,the influences of spatially varying stochastic properties on free vibration analysis of composite plates were investigated via development of a new approach named the deterministic-stochastic Galerkin-based semi-analytical *** material properties including tensile modulus,shear modulus,and density of the plate were assumed to be spatially varying and *** fields with first-order Markov kernels were utilized to define the aforementioned material *** stochastic fields were decomposed via application of the K arhunen-Loeve theorem.A first-order shear deformation theory was assumed,following which the displacement field was defined using admissible trigonometric modes to derive the potential and kinetic *** stochastic equations of motion of the plate were obtained using the variational *** deterministic-stochastic Galerkin-based method was utilized to find the probability space of natural frequencies,and the corresponding mode shapes of the plate were determined using a polynomial chaos *** proposed method significantly reduced the size of the mathematical models of the structure,which is very useful for enhancing the computational efficiency of stochastic *** methodology was verifed using a stochastic finite element method and the available results in *** sensitivity of natural frequencies and corresponding mode shapes due to the uncertainty of material properties was investigated,and the results indicated that the higher-order modes are more sensitive to uncertainty propagation in spatially varying properties.

关键词： composite plate spatially varying stochastic properties Galerkin method polynomial chaos approach semi-analytical approach

An Influence Statistic For Linear Measurement Error Models

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Acta Mathematicae Applicatae Sinica 2017年第3期33卷 619-632页

作者： hadi EMAMI Department of statistics University of ZanjanZanjanIran

Detection of multiple outliers or subset of influential points has been rarely considered in the linear measurement error models. In this paper a new influence statistic for one or a set of observations is generalized and characterized based on the corrected likelihood in the linear measurement error models. This influence statistic can be expressed in terms of the residuals and the leverages of linear measurement error regression. Unlike Cook＇s statistic, this new measure of influence has asymptotically normal distribution and is able to detect a subset of high leverage outliers which is not identified by Cook＇s statistic. As an illustrative example, simulation studies and a real data set are analysed.

关键词： cook's statistic corrected likelihood diagnostics leverages outlier

Data-driven estimation of joint roughness coefficient

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第6期13卷 1428-1437页

作者： hadi Fathipour-Azar Faculty of Mining Engineering Petroleum and GeophysicsShahrood University of TechnologyShahroodIran

Joint roughness is one of the most important issues in the hydromechanical behavior of rock ***,the joint roughness coefficient(JRC)estimation is of paramount importance in geomechanics engineering *** show that the application of statistical parameters alone may not produce a sufficiently reliable estimation of the JRC ***,alternative data-driven methods are proposed to assess the JRC *** this study,Gaussian process(GP),K-star,random forest(RF),and extreme gradient boosting(XGBoost)models are employed,and their performance and accuracy are compared with those of benchmark regression formula(i.e.Z2,Rp,and SDi)for the JRC *** analyze the models’performance,112 rock joint profile datasets having eight common statistical parameters(R_(ave),R_(max),SD_(h),iave,SD_(i),Z_(2),R_(p),and SF)and one output variable(JRC)are utilized,of which 89 and 23 datasets are used for training and validation of models,*** interpretability of the developed XGBoost model is presented in terms of feature importance ranking,partial dependence plots(PDPs),feature interaction,and local interpretable model-agnostic explanations(LIME)*** of results show that machine learning models demonstrate higher accuracy and precision for estimating JRC values compared with the benchmark empirical equations,indicating the generalization ability of the data-driven models in better estimation accuracy.

关键词： Joint roughness coefficient(JRC) Statistical parameters Gaussian process(GP) K-star Random forest(RF) Extreme gradient boosting(XGBoost) Correlation Machine learning(ML) Sensitivity analysis

New empirical model to evaluate groundwater flow into circular tunnel using multiple regression analysis

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International Journal of Mining Science and Technology 2017年第3期27卷 415-421页

作者： Farhadian hadi Katibeh Homayoon Departmen of Mining Engineering Faculty of Engineering University of Birjand Birjand Iran Department of Mining and Metallurgical Engineering Amirkabir University of Technology (Tehran Polytechnic) Tehran Iran

There are various analytical, empirical and numerical methods to calculate groundwater inflow into tun- nels excavated in rocky media. Analytical methods have been widely applied in prediction of groundwa- ter inflow to tunnels due to their simplicity and practical base theory. Investigations show that the real amount of water infiltrating into jointed tunnels is much less than calculated amount using analytical methods and obtained results are very dependent on tunnel＇s geometry and environmental situations. In this study, using multiple regression analysis, a new empirical model for estimation of groundwater seepage into circular tunnels was introduced. Our data was acquired from field surveys and laboratory analysis of core samples. New regression variables were defined after perusing single and two variables relationship between groundwater seepage and other variables. Finally, an appropriate model for estima- tion of leakage was obtained using the stepwise algorithm. Statistics like R, R2, R2e and the histogram of residual values in the model represent a good reputation and fitness for this model to estimate the groundwater seepage into tunnels. The new experimental model was used for the test data and results were satisfactory. Therefore, multiple regression analysis is an effective and efficient way to estimate the groundwater seeoage into tunnels.

关键词： Groundwater inflow Analytical equation Multiple regression analysis Stepwise algorithm Tunnel

Study of shape isomer yields of ^(240)Am in the framework of a dynamical-statistical model

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Chinese Physics C 2010年第11期34卷 1714-1716页

作者： hadi Eslamizadeh Department of Physics Persian Gulf University

A dynamical statistical model is used to analyze the experimental shape isomer yields data in the reaction d＋240Pu at E=20–29 *** possibility of determining the nuclear dissipation is *** of the experimental data wi... 详细信息

关键词： fission fission barrier reduced dissipation coeffcient

Histogram of the node strength and histogram of the edge weight: two new features for RGB-D person re-identification

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Science China(Information Sciences) 2018年第9期61卷 112-125页

作者： Zeynab IMANI hadi SOLTANIZADEH Electrical and Computer Engineering Faculty Semnan Univercity

Person re-identification is a classical task for any multi-camera surveillance system. Most of the existing researches on re-identification are based on features extracted from RGB images. However,there are many deficiencies in RGB image processing, some of which are requiring a lot of illumination and high computation. In this paper, novel features are proposed for RGB-D person re-identification. First, the complex network approach in texture recognition is modified and its threshold function is changed for using in depth images extracted by RGB-D sensors. Then, two novel measurements named the histogram of the edge weight(HEW) and the histogram of the node strength(HNS) are introduced on complex *** features fit both single-shot and multi-shot person re-identification. In the single-shot case, the HNS is extracted from only one frame while for the multi-shot case it is extracted from both one frame and multi-frames. These proposed measurements are called histogram of the spatial node strength(HSNS)and histogram of the temporal node strength(HTNS) respectively. Subsequently, these measurements are combined with skeleton features using score-level fusion. The method is evaluated using two benchmark databases and the results show that ours outperforms some state-of-the-art methods.

关键词： complex network edge weight graph node strength person re-identification skeleton features

Proposal of a probabilistic assessment of structural collapse concomitantly subject to earthquake and gas explosion

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Frontiers of Structural and Civil Engineering 2018年第3期12卷 425-437页

作者： Gholamreza ABDOLLAHZADEH hadi FAGHIHMALEKI Department of Civil Engineering Babol Noshirvani University of Technology Shariati Av. Babol Mazandaran Iran

In recent decades, many public buildings, located in seismic-prone residential areas, had to grapple with abnormal loads against which the structures were unguarded. In this piece of research, an ordinary three dimensional reinforced concrete building is selected as case study. The building is located in an earthquake-prone region; however, it is designed according to seismic building codes. Yet, it is not shielded against abnormal loads, such as blasts. It is assumed that the building suffers a blast load, due to mechanical/thermal installation failure during or after intense seismic oscillations. These two critical incidents are regarded codependent and compatible. So the researchers developed scenarios and tried to assess different probabilities for each scenario and carried out an analysis to ensure if progressive collapse had set in or not. In the first step, two analysis models were used for each scenario; a non-linear dynamic time history analysis and a blast local dynamic analysis. In the second step, having the structural destructions of the first step in view, a pushdown analysis was carried out to determine the severity of progressive collapse and assess building robustness. Finally, the annual probability of structural collapse under simultaneous earthquake and blast loads was estimated and offered.

关键词： gas blast pushdown analysis progressive collapse annual probability of structural collapse 3D model of structure