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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

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

Controlling Thermodynamic Properties of Ferromagnetic Group-Ⅳ Graphene-Like Nanosheets by Dilute Charged Impurity

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Communications in Theoretical Physics 2017年第5期67卷 569-576页

作者： mohsen Yarmohammadi Kavoos Mirabbaszadeh Department of Energy Engineering and Physics Amirkabir University of Technology Tehran Iran

Using the Kane-Mele Hamiltonian, Dirac theory and self-consistent Born approximation, we investigate the effect of dilute charged impurity on the electronic heat capacity and magnetic susceptibility of two-dimensional ferromagnetic honeycomb structure of group-Ⅳ elements including silicene, germanene and stanene within the Green's function approach. We also find these quantities in the presence of applied external electric field. Our results show that the silicene(stanene) has the maximum(minimum) heat capacity and magnetic susceptibility at uniform electric fields. From the behavior of theses quantities, the band gap has been changed with impurity concentration, impurity scattering strength and electric field. The analysis on the impurity-dependent magnetic susceptibility curves shows a phase transition from ferromagnetic to paramagnetic and antiferromagnetic phases. Interestingly, electronic heat capacity increases(decreases) with impurity concentration in silicene(germanene and stanene) structure.

关键词： ferromagnetic group-Ⅳ elements Green's function electronic heat capacity magnetic susceptibility phase transition

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

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

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

Proposing a novel geo-structural model for Torbat-e-Jam-Fariman plain(Northeast of Iran),based on Geomorphic indices calculation,conjugating the field evidences

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Journal of Mountain Science 2023年第5期20卷 1385-1401页

作者： mohsen JAMI Alireza DOCHESHMEH GORGIJ Mining Engineering Group Industry and Mining Faculty(khash)University of Sistan and Baluchesan+009854IRAN

There are various faults in northern and southern margins of Torbat-e-Jam-Fariman plain which show the probability of enormous earthquake in the *** present study the geomorphic indices contain Asymmetry Function(Af),Sinuosity of mountain front(Smf),Valley floor index(Vf),Hypsometric index(Hi),Mean Axial slope of channel index(MASC)and Drainage Basin Shape(Bs),have been utilized to determine the relative tectonic activity index(IAT)to recognize,eventually,the geo-structural model of the study *** and folds control the geo-structural activities of the study area,and the geomorphic indices are being affected in consequence of their *** intensity of these activities is different throughout the *** are many geomorphic evidences,related to active transform fault which are detectable all over the study area such as deviated rivers,quaternary sediments transformation,fault ***,recognition of geo-structural model of the study area is extremely *** study,then,approved the results of geomorphic indices calculation in determining the geo-structural model of the study *** depicted that the geostructural model of the study area is a kind of Horsetail splay form which is in accordance to the relative tectonic activity of the study *** on the above mentioned results it can be predicted that the splays are the trail of Neyshabour fault.

关键词： Fault Geo-structural Model Relative tectonic activity Geomorphic indices Horsetail Splay

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

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

Fouling of WO3 nanoparticle-incorporated PSf membranes in ultrafiltration of landfill leachate and dairy a combined wastewaters： An investigation using model

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Chinese Journal of Chemical Engineering 2017年第6期25卷 741-751页

作者： Majid Peyravi mohsen Jahanshahi Soodabeh Khalili Nanoenvironment Research Group Nanotechnology Institute Faculty of Chemical Engineering Babol Noshirvani University of Technolog~ Babol lran

As fouling has always been a major drawback of membrane technology, qualitative and quantitative understanding of membrane fouling mechanisms therefore becomes vital in order to help push membrane separation technologies forward. In this study, firstly, self-cleaning Polysulfone(PSf) membranes were synthesized by incorporation of WO_3nanoparticles(0–2 wt%) and subsequent UV irradiation for efficient ultrafiltration(UF)of landfill leachate and dairy wastewater. The membrane surface properties were characterized by scanning electron microscopy(SEM) and contact angle analysis. It was found that UV-irradiated membranes exhibited higher percent COD removals due to the hydrophilicity and photocatalytic properties of nano-WO_3. Subsequently, in order to analyze the fouling behavior of the membranes, a set of experimental data from cross-flow ultrafiltration of municipal landfill leachate and industrial dairy wastewater at 25 °C was obtained. A new model of membrane fouling was proposed based on a resistance in series concept and was fitted well with all experimental data *** all relative errors of prediction provided by the proposed model were less than 2.5%. In addition, it was revealed that this newly-developed model exhibited smooth transition between the common successive twostep pore blockage-cake filtration phenomena and thus eliminates the need to use separate equations for different mechanisms.

关键词： Fouling model Leachate wastewater Ultrafiltration Whey wastewater Chemical oxygen demand