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Landslide susceptibility mapping using machine learning algorithms and comparison of their performance at Abha Basin,Asir Region,Saudi Arabia

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Geoscience Frontiers 2021年第2期12卷 639-655页

作者： Ahmed Mohamed Youssef hamid Reza Pourghasemi Geology Department Faculty of ScienceSohag UniversityEgypt Geological Hazards Department Applied Geology SectorSaudi Geological SurveyP.O.Box 54141Jeddah21514Saudi Arabia Department of Natural Resources and Environmental Engineering College of AgricultureShiraz UniversityShirazIran

The current study aimed at evaluating the capabilities of seven advanced machine learning techniques(MLTs),including,Support Vector Machine(SVM),Random Forest(RF),Multivariate Adaptive Regression Spline(MARS),Artificial Neural Network(ANN),Quadratic Discriminant Analysis(QDA),Linear Discriminant Analysis(LDA),and Naive Bayes(NB),for landslide susceptibility modeling and comparison of their *** machine learning algorithms with spatial data types for landslide susceptibility mapping is a vitally important *** study was carried out using GIS and R open source software at Abha Basin,Asir Region,Saudi ***,a total of 243 landslide locations were identified at Abha Basin to prepare the landslide inventory map using different data *** the landslide areas were randomly separated into two groups with a ratio of 70%for training and 30%for validating *** landslide-variables were generated for landslide susceptibility modeling,which include altitude,lithology,distance to faults,normalized difference vegetation index(NDVI),landuse/landcover(LULC),distance to roads,slope angle,distance to streams,profile curvature,plan curvature,slope length(LS),and *** area under curve(AUC-ROC)approach has been applied to evaluate,validate,and compare the MLTs *** results indicated that AUC values for seven MLTs range from 89.0%for QDA to 95.1%for *** findings showed that the RF(AUC=95.1%)and LDA(AUC=941.7%)have produced the best performances in comparison to other *** outcome of this study and the landslide susceptibility maps would be useful for environmental protection.

关键词： Landslide susceptibility Machine learning algorithms Variables importance Saudi Arabia

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Estimation of highway capacity under environmental constraints *** traffic flow criteria:A case study of Tehran

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第5期8卷 751-761页

作者： hamid Mirzahossein Farshid Safari Erfan Hassannayebi Department of Civil Engineering-Transportation Faculty of Technical and EngineeringImam Khomeini International University(IKIU)Qazvin 34148-96818Iran Research Centre for Integrated Transport Innovation(rCITI) School of Civil and Environmental EngineeringUniversity of New South WalesSydneyNSW 2052Australia Department of Industrial Engineering Sharif University of TechnologyTehran 14588-89694Iran

In this paper,the concept of environmental capacity is developed to identify a convenient maximum traffic volume which will not reduce the life quality of *** presented method investigates the idea of traffic capacity under environmental constraints by calculating the maximum number of vehicles allowed on roads based on acceptable levels of air and noise *** this study,the permissible noise pollution level and permissible levels of CO and NOxpollution are considered for determining environmental *** show the significant difference between environmental capacity and functional traffic capacity,introduced by the highway capacity manual(HCM)as a conventional method for estimating functional ***,maximum allowed pollution is considered a constraint on a vehicle flow rate,which shows the proper traffic flow for selected streets in Tehran,Iran’s *** paper concludes that traffic capacity under noise and air pollution constraints is much less(approximately one-fourth and one-eighth for noise and air pollution respectively)than the current highway capacity estimated using HCM ***,to save the cities like Tehran from noise and air pollution,traffic flows should be limited to the level of environmental capacity by implementing some travel demand management(TDM)policies like road pricing.

关键词： Traffic engineering Environmental pollutions Environmental capacity estimation Admissible traffic flow Highway capacity manual(HCM)

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Impacts of wind erosion and seasonal changes on soil carbon dioxide emission in southwestern Iran

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Journal of Arid Land 2020年第4期12卷 690-700页

作者： Nadia KAMALI hamid SIROOSI Ahmad SADEGHIPOUR Rangeland Research Division Research Institute of Forests and RangelandsAgricultural ResearchEducation and Extension Organization(AREEO)Tehran 13185116Iran Rangeland Sciences Gorgan University of Agricultural Researches and Natural ResourcesGorgan ***Iran Desert Studies Faculty Semnan UniversitySemnan ***Iran

Wind erosion is one of the main drivers of soil loss in the world, which affects 20 million hectare land of Iran. Besides the soil loss, wind erosion contributes to carbon dioxide emission from the soil into the atmosphere. The objective of this study is to evaluate monthly and seasonal changes in carbon dioxide emission in four classes i.e., low, moderate, severe and very severe soil erosion and the interactions between air temperature and wind erosion in relation to carbon dioxide emission in the Bordekhun region, Boushehr Province, southwestern Iran. Wind erosion intensities were evaluated using IRIFR(Iran Research Institute of Forests and Ranges) model, in which four classes of soil erosion were identified. Afterward, we measured carbon dioxide emission on a monthly basis and for a period of one year using alkali traps in each class of soil erosion. Data on emission levels and erosion classes were analyzed as a factorial experiment in a completely randomized design with twelve replications in each treatment. The highest rate of emission occurred in July(4.490 g CO_2/(m^2·d)) in severely eroded lands and the least in January(0.086 g CO_2/(m^2·d)) in low eroded lands. Therefore, it is resulted that increasing erosion intensity causes an increase in soil carbon dioxide emission rate at severe erosion intensity. Moreover, the maximum amount of carbon dioxide emission happened in summer and the minimum in winter. Soil carbon dioxide emission was just related to air temperature without any relationship with soil moisture content;since changes of soil moisture in the wet and dry seasons were not high enough to affect soil microorganisms and respiration in dry areas. In general, there are complex and multiple relationships between various factors associated with soil erosion and carbon dioxide emission. Global warming causes events that lead to more erosion, which in turn increases greenhouse gas emission, and rising greenhouse gases will cause more global warming. The

关键词： alkali trap arid areas global warming IRIFR model soil biology

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ASYMPTOTIC CONVERGENCE OF A GENERALIZED NON-NEWTONIAN FLUID WITH TRESCA BOUNDARY CONDITIONS

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Acta Mathematica Scientia 2020年第3期40卷 700-712页

作者： Adelkader SAADALLAH hamid BENSERIDI Mourad DILMI Applied Mathematics Laboratory Department of MathematicsFaculty of SciencesUniversity of Ferhat Abbas-Sétif 119000Algeria

The goal of this article is to study the asymptotic analysis of an incompressible Herschel-Bulkley fluid in a thin domain with Tresca boundary *** yield stress and the constant viscosity are assumed to vary with respect to the thin layer parameterε.Firstly,the problem statement and variational formulation are *** then obtained the existence and the uniqueness result of a weak solution and the estimates for the velocity field and the pressure independently of the parameterε.Finally,we give a specific Reynolds equation associated with variational inequalities and prove the uniqueness.

关键词： Asymptotic approach Herschel-Bulkley fluid Reynolds equation Tresca law

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Exchange Coupling and Magnetic Behavior of SmCo_(5-x)Sn_x Alloys

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Journal of Materials Science & Technology 2011年第3期27卷 218-222页

作者： hamid Zaigham F.Ahmad Khalid Faculty of Materials Science and Engineering GIK Institute of Engineering Sciences and Technology

Exchange coupling and magnetic properties of SmCo5 alloys containing different amounts of Sn were investigated in sintered magnets. X-ray diffraction analysis revealed the formation of Sm2Co17 and Sm2Co7 phases in SmCo5 matrix. Exchange coupling mechanism was evaluated by switching field distribution, dcdemagnetization and magnetization curves as function of reverse applied field. Energy product of 59.2 kJ/m3 （7.4 MGOe）, remanent magnetization to maximum magnetization ratio of 0.97 and remanence coercivity to intrinsic coercivity ratio of 1.75 were achieved for 0.2 at.% Sn.

关键词： Nanocomposite magnet Nanocrystalline phases Sintering Exchange interactions

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Study the operating conditions on agglomeration of RDX particles in anti-solvent crystallization by using statistical optimization

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Defence Technology（防务技术） 2019年第2期15卷 233-240页

作者： hamid Reza Pouretedal Sajjad Damiri Ali Zandi Department of Chemistry Faculty of Science Malek-Ashtar University of Technology

The unfavorable growth and agglomeration of micro-particles of RDX explosive was almost observed in manufacture process. For preventing of growth of micro-particles and agglomeration in anti-solvent crystallization process, the effect of additives glucose, sucrose and poly ethylene glycol-2000 and wetting solvent of isopropyl alcohol were studied. Taguchi experimental design was used for optimization of the operating conditions. The type of additive, the amount of additive(%wt.), solvent of wetting and wetting time were selected for optimization of the conditions. By using 4 factor and 3 levels, 27 experiments were conducted(L27). Results showed that in the presence of 2 %wt. of sucrose additive and isopropyl alcohol solvent, the agglomerations of particles were decreased so that a decrease 30-50% in the average of particles size was seen. Addition additives were effective in storage container and for reduce the agglomeration of particles during storage. Also, the agglomeration rate of particles was reduced over time at optimized conditions. Imaging optical microscopy, scanning electron microscopy(SEM), and particle size analyzer(PSA) methods were used for particles size analyzing as a response in statistical optimization and quality control of the final product. The sensitivity to some mechanical and shock stimuli on the RDX in presence of sucrose additive was tested and the obtained results showed the insignificant effect of additive on the safety properties of pure RDX.

关键词： RDX explosive Taguchi experimental design Agglomeration Additive Anti-solvent

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Comments on “The feedback control of fractional order unified chaotic system”

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Chinese Physics B 2011年第9期20卷 107-109页

作者： Elham Amini Boroujeni hamid Reza Momeni Automation and Instruments Laboratory Electrical Engineering DepartmentTarbiat Modares UniversityTehranIran

Our comments point out some mistakes in the main theorem given by Yang and Qi in Ref. [1] concerning the equivalent passivity method to design a nonlinear controller for the stabilizing fractional order unified chaotic system. The proof of this theorem is not reliable, since the mathematical basis of the fractional order calculus is not considered. Moreover, there are some algebraic mistakes in the inequalities used, thus making the proof invalid. We propose a proper Lyapunov function and the stability of Yang and Qi＇s Controller is investigated based on the fractional order Lyapunov theorem.

关键词： fractional order calculus Lyapunov function

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Increasing of photostability of HNS explosive in the presence of UV photostabilizers

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Defence Technology（防务技术） 2021年第2期17卷 338-342页

作者： hamid Reza Pouretedal Sajjad Damiri Zynab Karami Faculty of Applied Sciences Malek Ashtar University of TechnologyIran

The photostabilies of hexanitrostillbene(HNS)were studied at 1%*** *** photostabilizers of Chiguard BP-12(UV-531),ADK STAB LA-326(UV-326),ADK STAB LA-32(UV-P),Irganox 1010 and Everstab LS944 were used in this study.A photoreactor including a 30 W monochromatic UV lamp was used for investigation of photodegradations of solid *** changes in surface area of HNS peak in HPLC chromatogram at time intervals of 2,4,6 and 8 h were used for calculation of kinetic rate constants of photodegradation *** compound of UV-P photostabilizer was found to have the greatest effect on enhancing photostability for HNS among the investigated *** kinetic rate constants were obtained 6.2×10^(-2) and 4.1×10^(-2)h^(-1),respectively,for photodegradation process of HNS in absence and in presence of UV-P.

关键词： HNS explosive Photodegradation Photostabilizer Kinetic rate constant

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Tribological Properties of Nanostructured Al/Al_(12)(Fe,V)_3Si Alloys

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Acta Metallurgica Sinica(English Letters) 2015年第1期28卷 83-92页

作者： hamid Ashrafi Mohammad Hosein Enayati Rahmatollah Emadi Department of Materials Engineering Isfahan University of TechnologyIsfahan 84156-83111 Iran

Tribological behavior of nanostructured pure Al and Al–Al12（Fe,V）3Si alloys containing 27（FVS0812） and 37（FVS1212） vol% of Al12（Fe,V）3Si precipitates was investigated. All samples were prepared using mechanical alloying followed by hot pressing. Wear tests were performed at room temperature using a pin-on-disk machine. Results showed that the presence of Al12（Fe,V）3Si precipitates increases the wear resistance of nanostructured Al, and the wear resistance increases with increasing the Al12（Fe,V）3Si content. Scanning electron microscopy images of worn surfaces and wear debris demonstrated that abrasion and adhesion are the governing wear mechanisms for the nanostructured FVS0812 alloy at 2 and 5 N normal loads, whereas for the nanostructured FVS1212 alloy, the dominant wear mechanism is abrasion at these loads. A mechanically mixed layer（MML） containing Fe and O was formed on the worn surfaces of FVS0812 and FVS1212 samples at 10 N normal load. Formation and delamination of MML controls the wear behavior of these samples at the normal load of 10 N. It is also found that the presence of Al12（Fe,V）3Si precipitates decreases the friction coefficient of nanostructured Al.

关键词： Al–Fe–V–Si alloy Wear Scanning electron microscopy

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Fabrication of Fullerene-Reinforced Aluminum Matrix Nanocomposites

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Acta Metallurgica Sinica(English Letters) 2017年第10期30卷 973-982页

作者： Hamed Asgharzadeh hamid Faraghi Hyoung Seop Kim Department of Materials Engineering Faculty of Mechanical EngineeringUniversity of Tabriz Department of Materials Science and Engineering Pohang University of Science and Technology (POSTECH)

Fullerene-reinforced A1 matrix nanocomposites were fabricated by high-energy mechanical milling followed by consolidation through hot extrusion or high-pressure torsion（HPT）. The results indicate that a relatively homogeneous microstructure consisting of elongated, micrometer-sized A1 grains is formed in the hot-extruded specimens. However, the microstructure is not uniform along the radius of the HPT disks, which includes coarse grains near the center of the disk and ultrafine grains in the middle and along the edge of the specimen. Microstructural evaluations of the HPT disks indicate that A1 grain refinement occurs due to the addition of fullerene, as grain size is reduced to 60 nm from 118 nm. The formation of the harmful aluminum carbide phase is not detected during the fabrication of Al/C（60） nanocomposites. The hardness, yield stress, and ultimate tensile strength of the Al-2 vol.% C（60） nanocomposites are about 27-160% higher than those of the monolithic A1 samples, revealing the effective strengthening of fullerene particles in A1 matrix. Moreover,mechanical properties of the Al/fullerene nanocomposites are significantly enhanced（59-272%） by utilizing HPT in comparison to hot-extruded specimens due to their much finer A1 grain structure. The reduction in the number and the size of the dimples, as well as the formation of smooth regions on the tensile fracture surface of Al/C（60）, results in their overall lower ductility compared to monolithic Al.

关键词： Aluminum Fullerene High-pressure torsion Hot extrusion Microstructure Mechanical properties

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