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Modelling the spatial distribution of snake species in northwestern Tunisia using maximum entropy(Maxent) and Geographic Information System(GIS)

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Journal of Forestry Research 2018年第1期29卷 233-245页

作者： mohsen Kalboussi Hammadi Achour Institut Sylvo-pastoral de Tabarka Universit6 de Jendouba8110 Tabarka Tunisia Unite de recherche 《Geomatique des Geosystemes》 02/UR/10-01 Universite de la Mannouba Campus universitaire B.P. 95 2010 Mannouba Tunisia

We used GIS and maximum entropy to predict the potential distribution of six snake species belong to three families in Kroumiria（Northwestern Tunisia）： Natricidae（Natrix maura and Natrix astreptophora）, Colubridae（Hemorrhois hippocrepis, Coronella girondica and Macroprotodon mauritanicus）, and Lamprophiidae（Malpolon insignitus）. The suitable habitat for each species was modelled using the maximum entropy algorithm, combining presence field data（collected during 16 years：2000–2015） with a set of seven environmental variables（mean annual precipitation, elevation, slope gradient,aspect, distance to watercourses, land surface temperature and normalized Differential Vegetation Index. The relative importance of these environmental variables was evaluated by jackknife tests and the predictive power of our models was assessed using the area under the receiver operating characteristic. The main explicative variables of the species distribution were distance from streams and elevation, with contributions ranging from 60 to 77 and from 10 to 25%,respectively. Our study provided the first habitat suitability models for snakes in Kroumiria and this information can be used by conservation biologists and land managers concerned with preserving snakes in Kroumiria.

关键词： Species distribution modelling Maxent Snakes Kroumiria Tunisia

Heavy Metal Release from Some Industrial Wastes: Influence of Organic and Inorganic Acids, Clay Minerals, and Nanoparticles

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Pedosphere 2018年第1期28卷 70-83页

作者： Marzieh TAGHIPOUR mohsen JALALI Department of Soil Science College of Agriculture Bu-Ali Sina University

Knowledge about heavy metal release from industrial solid wastes(ISWs) is crucial for better management of their environmental risks. This study was conducted to investigate the effect of organic and inorganic acids, clay minerals, and nanoparticles(NPs) on the release of heavy metals from sugar factory waste, ceramic factory waste, leather factory waste, and stone cutting waste. The influence of the extractants on heavy metal release from these ISWs was in the following descending order: citric acid > oxalic acid > nitric acid≥ sulfuric acid > Ca Cl2. Addition of clay minerals and NPs as adsorbents decreased heavy metal release, which was significantly lower in NP-treated wastes than in the clay mineral-treated wastes. On the other hand, the presence of organic and inorganic acids increased heavy metal adsorption by NPs and clay minerals. These results suggest that NPs can be applied successfully in waste remediation,and organic and inorganic acids play an important role in the removal of heavy metals from the studied adsorbents.

关键词： adsorbents environmental risks extractants industrial solid wastes metal removal remediation

An Approximate Approach for Systems of Singular Volterra Integral Equations Based on Taylor Expansion

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Communications in Theoretical Physics 2018年第8期69卷 145-152页

作者： mohsen Didgar Alireza Vahidi Department of Mathematics Guilan Science and Research Branch Islamic Azad University Department of Mathematics Rasht Branch Islamic Azad University Department of Mathematics College of Science Yadegar-e-Emam Khomeyni (RAH) Shahr-e-Rey Branch Islamic Azad University

In this article, an extended Taylor expansion method is proposed to estimate the solution of linear singular Volterra integral equations systems. The method is based on combining the m-th order Taylor polynomial of unknown functions at an arbitrary point and integration method, such that the given system of singular integral equations is converted into a system of linear equations with respect to unknown functions and their derivatives. The required solutions are obtained by solving the resulting linear system. The proposed method gives a very satisfactory solution,which can be performed by any symbolic mathematical packages such as Maple, Mathematica, etc. Our proposed approach provides a significant advantage that the m-th order approximate solutions are equal to exact solutions if the exact solutions are polynomial functions of degree less than or equal to m. We present an error analysis for the proposed method to emphasize its reliability. Six numerical examples are provided to show the accuracy and the efficiency of the suggested scheme for which the exact solutions are known in advance.

关键词： systems of singular Volterra integral equations (SSVIEs) systems of generalized Abel's integral equations error analysis Taylor expansion

Cell morphology,porosity,microstructure and mechanical properties of porous Fe–C–P alloys

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International Journal of Minerals,Metallurgy and Materials 2021年第2期28卷 257-265页

作者： Hamid Sazegaran Seyyed mohsen Moosavi Nezhad Department of Industrial Engineering Faculty of EngineeringQuchan University of TechnologyQuchan ***Iran Department of Metallurgy and Materials Engineering Faculty of EngineeringUniversity of GonabadGonabad ***Iran

Open cell steel foams were successfully fabricated through the powder metallurgy route using urea granules as the water leachable space holder in the present *** influence of different amounts of phosphorus(0,0.5wt%,1wt%,2wt%,and 4wt%)was investigated on the cell morphology,porosity,microstructure of cell walls,and mechanical properties of steel *** cell morphology and microstructure of the cell walls were evaluated using an optical microscope equipped with image processing software and a scanning electron microscope equipped with an energy dispersive X-ray *** addition,the compression tests were conducted on the steel foams using a universal testing *** on microscopic images,the porous structure consists of spherical cells and irregularly shaped pores that are distributed in the cell *** results indicated that by increasing the phosphorus content,the porosity increases from 71.9%to 83.2%.The partially distributed ferrite and fine pearlite was observed in the microstructure of the cell walls,andα-Fe and Fe3P eutectic extended between the boundaries of agglomerated iron ***,elastic and long saw-toothed plateau regions were observed before fracture in the compressional stress–strain *** to the results,by increasing the phosphorus content from 0 to 4wt%,the plateau region of the stress–strain curves shifts to the right and ***,increasing phosphorus content causes improvement in the mechanical properties of steel foams.

关键词： steel foam phosphorus space holder technique microstructure compressive behavior

Investigation of Io's auroral hiss emissions due to its motion in Jupiter's magnetosphere

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Research in Astronomy and Astrophysics 2012年第6期12卷 693-702页

作者： mohsen H.Moghimi Department of Aerospace Engineering Sharif University of TechnologyTehranIran

The left-hand side of the auroral hiss emission observed by Galileo has a frequency time profile shaped very similar to the funnel shape observed in the Earth＇s auroral region. This close similarity indicates that we can use the theory of whistler- mode propagation near the resonance cone to locate the emission source. The general characteristics of the whistler mode are discussed. Then the position of the emission source is investigated using a geometrical method that takes into account the trajectory of Galileo. Initially a point source is assumed. Then the possibility of a sheet source aligned along the magnetic field lines which tigated. Both types of sources show that the close to the surface of Io. are tangent to the surface of Io is inves- whistler mode radiation originates veryclose to the surface of Io.

关键词： data analysis -- detectors -- magnetic fields -- spectrographs

Interconnection and damping assignment and Euler-Lagrange passivity-based control of photovoltaic/battery hybrid power source for stand-alone applications

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第9期12卷 774-786页

作者： Ali TOFIGHI mohsen KALANTAR Department of Electrical Engineering Pardis BranchIslamic Azad UniversityPardisIran Center of Excellence for Power System Automation and Operation Department of Electrical EngineeringIran University of Science and TechnologyTehranIran

A DC hybrid power source composed of photovoltaic cells as the main power source,Li-ion battery storage as the secondary power source,and power electronic interface,is modeled based on port-controlled Hamiltonian systems and Euler-Lagrange ***,passivity-based controllers are *** asymptotic stability is ensured as *** addition,a power management system is designed to manage power flow between *** and simulation of the proposed hybrid power source is accomplished using MATLAB/*** interest is focused on the comparison of the two passivity-based control methods and their use in hybrid power systems.

关键词： DC hybrid power source Euler-Lagrange (EL) equations Interconnection and damping assignment (IDA) Passivity-based control Photovoltaic Li-ion battery

Evaluation of restoration success in arid rangelands of Iran based on the variation of ecosystem services

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Journal of Arid Land 2023年第11期15卷 1290-1314页

作者： mohsen SHARAFATMANDRAD Azam KHOSRAVI MASHIZI Department of Ecological Engineering Faculty of Natural ResourcesUniversity of JiroftJiroft ***Iran

The plantation of non-native species is one of the most expensive ecological restoration measures in arid and semi-arid areas,while its impacts on local communities are largely *** study assessed the rate of change and the dynamic degree of the economic values of ecosystem services related to local conservation(water yield,stocking rate and aesthetic value)and preserving the future(carbon sequestration,soil protection,soil stability and habitat provision)to determine the restoration success of the plantation of non-native species Haloxylon ammodendron(***.)Bunge ex Fenzl(15-and 30-year-old)in parts of arid rangelands of Bardsir region,Kerman Province,*** investigated the impacts of the two plantations on the seven ecosystem services and ecosystem structures(horizontal and vertical structures,vegetation composition and species diversity)based on field sampling and measurements at four sampling sites(i.e.,control,degraded,and 15-and 30-year-old plantation sites)in spring and summer of *** restoration success of the plantation of non-native species was then examined by assessing the rate of change and the dynamic degree of the total economic value of all ecosystem services as well as the rate of change and the dynamic degree of the economic values of ecosystem services for the two groups(local conservation and preserving the future).Although the plantation of non-native species *** enormously improved the vertical and horizontal structures of ecosystems,it failed to increase species diversity and richness ***,despite the plantation of non-native species *** had significantly increased the economic values of all ecosystem services,it was only quite successful in restoring carbon *** analysis showed that plantation age had a significant impact on restoration success directly and indirectly(through changing ecosystem structures and services).The dynamic degree of the economic values of ecosystem services r

关键词： Haloxylon ammodendron restoration success ecosystem services ecosystem structures arid ecosystems path analysis Iran

Exemplar-based video inpainting with large patches

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第4期11卷 270-277页

作者： Abbas KOOCHARI mohsen SORYANI Department of Computer Engineering Iran University of Science and Technology

Inpainting is the process of reconstructing damaged regions of images and video *** study deals with weaknesses of the current video inpainting techniques,when an object is totally damaged,and a framework for video inpainting is *** this framework,the moving object is separated from the background.A large mosaic image is constructed using the moving object and then a patch-based method with large patches is used to fill *** each frame,the inpainted foreground is obtained by placing the object in its *** areas of the stationary background are also filled separately and the final video is produced by composing the inpainted background and object *** for three video sequences with an occluded object show that this approach represents the object in the missing region better than other approaches.

关键词： Video inpainting Patch Background modeling Mosaic

Geochronological Constraints on the Haftcheshmeh Porphyry Cu-Mo-Au Ore Deposit, Central Qaradagh Batholith, Arasbaran Metallogenic Belt, Northwest Iran

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Acta Geologica Sinica(English Edition) 2017年第6期91卷 2109-2125页

作者： Shohreh HASSANPOUR mohsen MOAZZEN Department of Geology Payame Noor University Natural Science Faculty Geology DepartmentTabriz University

The Haftcheshmeh porphyry Cu-Mo-Au deposit in the Arasbaran metallogenic belt （AMB） of NW Iran contains more than 185 Mt of ore, with a grade ranging from 0.3% to 0.4%. It is hosted within a porphyritic diorite to granodiorite intruded into an older gabbro - diorite intrusion. 40Ar/39Ar analyses of primary magmatic hornblende from the granodiorite porphyry and gabbro - diorite show plateau ages of 26.41 ± 0.59 Ma, with an inverse isochron age of 25.9 ± 1.0 Ma and a plateau age of 27.47 ± 0.17 Ma, with an inverse isochron age of 27.48 ± 0.35 Ma for these two rock types, respectively. Comparing these new age data with those from the nearby Sungun （20.69 ± 0.35 Ma） and Kighal porphyry deposits defines a northwest-southeast Cu-Mo-Au mineralization zone extending for 20 km over the time span of-27 to 20 Ma. Geochemically, Haftcheshmeh rocks are calc-alkaline with high potassium affinities with tectonic setting in relation to volcanic arc setting. Large ion lithophile elements （LILE） such as Th, U and K show enrichment on a primitive mantle normalized diagram （specially Pb）, and are depleted in high field strength elements （HFSE） such as Ti and Nb, pointing to a mantle magma source contamination with crustal materials by subducted oceanic crust.

关键词： 40Ar/39Ar dating Haftcheshmeh porphyry Cu-Mo deposit Arasbaran Metallogenic Belt,Northwest Iran