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A New Integrable (2+1)-Dimensional Generalized Breaking Soliton Equation:N-Soliton Solutions and Traveling Wave Solutions

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Communications in Theoretical Physics 2016年第10期65卷 385-388页

作者： Abdul-majid Wazwaz Department of Mathematics Saint Xavier University

In this work,we study a new(2+1)-dimensional generalized breaking soliton equation which admits the Painleve property for one special set of *** derive multiple soliton solutions,traveling wave solutions,and periodic ... 详细信息

关键词： soliton breaking simplified traveling bilinear singular earlier ordinary auxiliary chaos

Homogeneity analysis of streamflow records in arid and semi-arid regions of northwestern Iran

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Journal of Arid Land 2018年第4期10卷 493-506页

作者： majid KAZEMZADEH Arash MALEKIAN University of Tehran Karaj 31587-77871Iran

Homogeneity analysis of the streamflow time series is essential to hydrological modeling, water resources management and climate change studies. In this study, five absolute homogeneity tests and one clustering approach were used to determine the homogeneity status of the streamflow time series （over the period 1960-2010） in 14 hydrometric stations of three important basins （i.e., Aras River Basin, Urmia Lake Basin and Sefid-Roud Basin） in northwestern Iran. Results of the Buishand range test, yon Neumann ratio test, cumulative deviation test, standard normal homogeneity test and Pettitt test for monthly streamflow time series detected that about 42.26%, 38.09%, 33.33%, 39.28% and 68.45% of the streamflow time series were inhomogeneous at the 0.01 significance level, respectively. Streamflow time series of the stations located in the eastern parts of the study area or within the Urmia Lake Basin were mostly homogeneous. In contrast, streamflow time series in the stations of the Aras River Basin and Sefied-Roud Basin showed inhomogeneity at annual scales. Based on the overall classification for the monthly and annual streamflow series, we determined that about 45.60%, 11.53% and 42.85% of the time series were categorized into the ＇useful＇, ＇doubtful＇ and ＇suspect＇ classes according to the five absolute homogeneity tests. We also found the homogeneity patterns of the streamflow time series by using the clustering approach. The results suggested the effectiveness of the clustering approach for homogeneity analysis of the streamflow time series in addition to the absolute homogeneity tests. Moreover, results of the absolute homogeneity tests and clustering approach indicated obvious decreasing change points of the streamflow time series in the 1990s over the three basins, which were mostly related to the hydrological droughts.

关键词： streamflow time series homogeneity test clustering analysis inhomogeneity Urmia Lake northwestern Iran

The distribution and frequency of damage to roadside trees in low-volume road construction

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Journal of Forestry Research 2018年第1期29卷 221-226页

作者： majid Lotfalian Mehran Nasiri Department of Forestry Faculty of Natural Resources Sari University of Agricultural Sciences and Natural Resources

We investigated the distribution and frequency of damage to tree stands adjacent to low-volume roads according to the type of hillside materials involved（soil or rock） and hillside gradient in mountainous forests of northern Iran. A total of 80 plots were systematically and randomly sampled to record damaged trees（bending,crushing and wounding） by class of hillside gradient and materials at the edge of road. Tree wounding and crushing at rock slopes was significantly greater than at hillsides with a mix of clay soil（p ／ 0.05）. Damage on hillsides with slope gradients[45% were 2, 8.5 and 2.3 times more frequent than on hillsides with slope gradient／15% for bending, crushing and wounding, respectively. The damage distribution varied according by type and the most frequent damage was tree wounding（p ／ 0.05）. The damage distribution was measured at distances of 4, 5 and 8 m from the road fillslope for tree bending, crushing and wounding, respectively. Using hydraulic excavators and physical barriers（wooden obstruction and synthetic holder） during earthworks for road construction could reduce these damage.

关键词： Low-volume road construction Tree damage Hillside materials Gradient Distribution

Antifouling nanocomposite polymer coatings for marine applications:A review on experiments,mechanisms,and theoretical studies

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Journal of Materials Science & Technology 2022年第23期118卷 73-113页

作者： Sepideh Pourhashem Abdolvahab Seif Farhad Saba Elham Garmroudi Nezhad Xiaohong Ji Ziyang Zhou Xiaofan Zhai majid Mirzaee Jizhou Duan Alimorad Rashidi Baorong Hou Key Laboratory of Marine Environmental Corrosion and Bio-fouling Institute of OceanologyChinese Academy of SciencesQingdao 266071China Open studio for marine Corrosion and Protection Pilot National Laboratory for Marine Science and TechnologyQingdao 266237China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Nanotechnology Research Center Research Institute of Petroleum Industry(RIPI)West Entrance Blvd.Olympic VillageTehranIran Department of Materials Science and Engineering Engineering FacultyFerdowsi University of MashhadMashhadIran University of Chinese Academy of Sciences Beijing 100039China Non-Metallic Materials Research Group Niroo Research InstituteTehran 14665517Iran

Marine fouling is a worldwide challenge with huge damages on industrial structures,side effects on economics of industries,and environmental and safety-related *** approaches have been used for combating fouling in the marine ***,nanocomposite polymer coatings are a novel generation of antifouling coatings with merits of toxin-free chemical composition and ease of large-scale *** such as nano-metals,nano-metal oxides,metal-organic frameworks,carbon-based nanostructures,MXene,and nanoclays have antibacterial and antifouling properties in the polymer ***,these nanomaterials can improve the corrosion resistance,mechanical strength,weathering stability,and thermal resistance of the polymer ***,in this review paper,the antifouling nanocomposite coatings are introduced and antifouling mechanisms are *** review explicitly indicates that the antifouling efficiency of the nanocomposite coatings depends on the properties of the polymer matrix,the inherent properties of the nanomaterials,the weight percent and the dispersion method of the nanomaterials within the coating matrix,and the chemicals used for modifying the surface of the nanomaterials;meanwhile,the hybrids of different nanomaterials and appropriate chemical agents could be used to improve the antifouling behavior of the prepared ***,the theoretical studies are introduced to pave the way of researchers working on theantifouling coatings,and the importance of the theoretical studies and computational modeling along with the experimental research is notified to develop antifouling coatings with high efficiency.

关键词： Antifouling nanocomposite coatings Nano-metal oxides Carbon-based nanomaterials MXene and nanoclays Theoretical studies

Handheld diffuse optical breast scanner probe for cross-sectional imaging of breast tissue

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Journal of Innovative Optical Health Sciences 2019年第2期12卷 74-85页

作者： majid Shokoufi Farid Golnaraghi School of Mechatronic Systems Engineering Simon Fraser University 250-13450102nd Avenue SurreyCanadaBC V3T 0A3

Diffuse optical spectroscopy is a relatively new,noninvasive and nonionizing technique for breast cancer *** the present study,we have introduced a novel handheld diffuse optical breast scan(DOB-Scan)probe to measure optical properties of the breast in vivo and create functional and compositional images of the *** addition,the probe gives more information about breast tissue's constituents,which helps distinguish a healthy and cancerous *** symmetrical light sources,each including four different wavelengths,are used to illuminate the breast tissue.A high-resolution linear array detector measures the intensity of the back-scattered photons at different radial destinations from the illumination sources on the surface of the breast tissue,and a unique image reconstruction algorithm is used to create four cross-sectional images for four different *** fromfiber optic-based illumination techniques,the proposed method in this paper integrates multi-wavelength light-emitting diodes to act as pencil beam sources into a scattering medium like breast *** unique design and its compact structure reduce the complexity,size and cost of a potential *** the introduced technique miniaturizes the probe,this study points to the reliability of this technique in the phantom study and clinical breast *** have received ethical approval to test the DOB-Scan probe on patients and we are currently testing the DOB-Scan probe on subjects who are diagnosed with breast cancer.

关键词： Breast cancer diffuse optical spectroscopy image reconstruction techniques medical and biological imaging optical breast phantom

A New Approach to Plane Failure of Rock Slope Stability Based on Water Flow Velocity in Discontinuities for the Latian Dam Reservoir Landslide

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Journal of Mountain Science 2011年第2期8卷 124-130页

作者： Morteza AHMADI majid ESLAMI Department of Mining Engineering Tarbiat Modares University Ghaem Consulting Engineers

The stability of slopes is always of great concern in the field of rock engineering. The geometry and orientation of pre-existing discontinuities show a larger impact on the behavior of slopes that is often used to describe the measurement of the steepness, incline, gradient, or grade of a straight line. One of the structurally controlled modes of failure in jointed rock slopes is plane failure. There are numerous analytical methods for the rock slope stability including limit equilibrium, stress analysis and stereographic methods. The limiting equilibrium methods for slopes under various conditions against plane failure have been previously proposed by several investigators. However, these methods do not involve water pressure on sliding surfaces assessments due to water velocity and have not yet been validated by case study results. This paper has tried to explore the effects of forces due to water pressure on discontinuity surfaces in plane failure through applying the improved equations. It has studied the effect of water flow velocity on sliding surfaces in safety factor, as well. New equations for considering water velocity (fluid dynamics) are presented. To check the validity of the suggested equations, safety factor for a case study has been determined. Results show that velocity of water flow had significant effect on the amount of safety factor. Also, the suggested equations have higher validity rate compared to the current equations.

关键词：水库滑坡水流速度边坡稳定性飞机故障不连续性法平面极限平衡方法大坝

Development of a handheld diffuse optical breast cancer assessment probe

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Journal of Innovative Optical Health Sciences 2016年第2期9卷 31-40页

作者： majid Shokoufi Farid Golnaraghi School of Mechatronic Systems Engineering Simon Fraser University 250-13450102 Avenue SurreyCanadaBC V3T 0A3

Diffuse Optical Spectroscopy(DOS)is a promising non-invasive and non-ionizing technique for breast anomaly *** this study,we have developed a new handheld DOS probe to measure optical properties of breast *** the proposed probe,the breast tissue is illuminated with four near infrared(NIR)wavelengths light emitting diodes(LED),which are encapsulated in a package(eLEDs),and two PIN photodiodes measure the intensity of the scattered photons at two di®erent *** proposed technique of using eLEDs is introduced,in order to have a multi-wavelength pointed-beam illumination source instead of using the laser-coupledflberoptic technique,which increases the complexity,size,and cost of the *** the fact that the proposed technique miniaturizes the probe and reduces the complexity of the DOS,the study proves that it is accurate and reliable in measuring optical properties of the *** measurements are performed at the rate of 10 Hz which is suitable for dynamic measurement of biological activity,*** multi-spectral evaluation algorithm is used to reconstruct four main absorber concentrations in the breast including oxy-hemoglobin(cHb),deoxy-hemoglobin(cHbO_(2)),water(cH2O),fat(cFat),and average scattering coeficient of the medium,as well as concentration changes in Hb(cHb)and HbO_(2)(cHbO_(2)).Although the probe is designed for breast cancer diagnosis,it can be used in a wide range of applications for both static and dynamic measurements such as functional brain imaging.A series of phantoms,comprised of Delrinr,Intralipidr,PierceTM and Black ink,are used to verify performance of the *** probe will be tested on human subjects,in-vivo,in the next phase.

关键词： Breast cancer diffuse optical spectroscopy intrinsic optical contrast hemoglobin concentration optical breast phantom

Assessing the impacts of current and future changes of the planforms of river Brahmaputra on its land use-land cover

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Geoscience Frontiers 2023年第4期14卷 100-122页

作者： Jatan Debnath Dhrubajyoti Sahariah Durlov Lahon Nityaranjan Nath Kesar Chand Gowhar Meraj Pankaj Kumar Suraj Kumar Singh Shruti Kanga majid Farooq Department of Geography Gauhati UniversityJalukbariAssamIndia GB Pant National Institute of Himalayan Environment(NIHE) Himachal Regional Centre(Himachal Pradesh)KulluIndia Department of Ecology Environment and Remote SensingGovernment of Jammu and KashmirKashmir 190018India Institute for Global Environmental Strategies Hayama 240-0115Japan Centre for Sustainable Development Suresh Gyan Vihar UniversityJaipur 302017India Centre for Climate Change and Water Research(C3WR) Suresh Gyan Vihar UniversityJaipur 302017India Department of Geography School of Environment and Earth SciencesCentral University of PunjabVPO-GhuddaBathinda 151401India

River bankline migration is a frequent phenomenon in the river of the floodplain ***,channel dynamics-related changes in land use and land cover(LULC)are becoming a risk to the life and property of people living in the vicinity of rivers.A comprehensive evaluation of the causes and consequences of such changes is essential for better policy and decision-making for disaster risk reduction and *** present study assesses the changes in the Brahmaputra River planform using the GIS-based Digital Shoreline Analysis System(DSAS)and relates it with the changing LULC of the floodplain evaluated using the CA-Markov *** this study,the future channel of the Brahmaputra River and its flood plain’s future LULC were forecasted to pinpoint the erosion-vulnerable ***-eight years(1973–2021)of remotely sensed data were applied to estimate the rate of bankline *** was observed that the river’s erosion-accretion rate was higher in early times than in more recent *** left and right banks’average shifting rates between 1973 and 1988 were -55.44 m/y and -56.79 m/y,respectively,while they were-17.25 m/y and -48.49 m/y from 2011 to *** left bank of the river Brahmaputra had more erosion than the right,which indicates that the river is shifting in the leftward direction(Southward).In this river course,zone A(Lower course)and zone B(Middle course)were more adversely affected than zone C(Upper course).According to the predicted result,the left bank is more susceptible to bank erosion than the right bank(where the average rate of erosion and deposition was -72.23 m/y and 79.50 m/y,respectively).The left bank’s average rate of erosion was -111.22 m/*** research assesses the LULC study in conjunction with river channel dynamics in vulnerable areas where nearby infrastructure and settlements were at risk due to channel *** degree of accu-racy was verified using the actual bankline and predicted bankline,as well as the actual LULC map

关键词： Channel shifting Erosion-Accretion Bankline Prediction DSAS CA-Markov Brahmaputra River

Isomorphisms of Finite Semi-Cayley Graphs

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Acta Mathematica Sinica,English Series 2015年第4期31卷 715-730页

作者： majid AREZOOMAND Bijan TAERI Department of Mathematical Sciences Isfahan University of Technology

Let G be a finite group. A Cayley graph over G is a simple graph whose automorphism group has a regular subgroup isomorphic to G. A Cayley graph is called a CI-graph （Cayley iso- morphism） if its isomorphic images are induced by automorphisms of G. A well-known result of Babai states that a Cayley graph F of G is a CI-graph if and only if all regular subgroups of Aut（F） isomorphic to G are conjugate in Aut（F）. A semi-Cayley graph （also called bi-Cayley graph by some authors） over G is a simple graph whose automorphism group has a semiregular subgroup isomorphic to G with two orbits （of equal size）. In this paper, we introduce the concept of SCI-graph （semi-Cayley isomorphism） and prove a Babai type theorem for semi-Cayley graphs. We prove that every semi-Cayley graph of a finite group G is an SCI-graph if and only if G is cyclic of order 3. Also, we study the isomorphism problem of a special class of semi-Cayley graphs.

关键词： Semi-Cayley graph Cayley graph CI-graph semiregular subgroup