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Progress in Natural Science:Materials International 2015年第5期25卷 392-398页

作者： t.Sivaraman v.Narasimman v.S.Nagarethinam A.R.Balu PG and Research Department of Physics A.V.V.M Sri Pushpam College

CdS and chlorine doped CdS(CdS:Cl) thin films with different Cl-doping levels(0,2,4,6 and 8 at%) have been deposited on glass substrates by a spray pyrolysis technique using a perfume *** effect of Cl doping on the structural,morphological,optical and electrical properties of the films was *** patterns revealed that all the films exhibit hexagonal crystal structure with a preferential orientation along the(0 0 2) plane irrespective of the Cl doping *** particle size value decreases from 22.03 nm to 18.12 nm with increase in Cl *** band gap is blue-shifted from 2.48 ev to 2.73 ev with increase in Cl doping *** the films have resistivity in the order of 10～4 Ω *** obtained results confirm that chlorine as an anionic dopant material can enhance the physical properties of CdS thin films to a large extent.

关键词： X-ray diffraction Crystal structure Preferential orientation thin films Optical band gap

A Convolutional Neural Network Classifier vGG-19 Architecture for Lesion Detection and Grading in Diabetic Retinopathy Based on Deep Learning

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Computers, Materials & Continua 2021年第1期66卷 827-842页

作者： v.Sudha t.R.Ganeshbabu Department of Electronics and Communication Engineering Pavai College of TechnologyNamakkal637018India Department of Electronics and Communication Engineering Muthayammal Engineering CollegeRasipuram637408India

Diabetic Retinopathy(DR)is a type of disease in eyes as a result of a diabetic condition that ends up damaging the retina,leading to blindness or loss of *** and physiological retinal variations involving slowdown of blood flow in the retina,elevation of leukocyte cohesion,basement membrane dystrophy,and decline of pericyte cells,*** DR in its initial stage has no symptoms,early detection and automated diagnosis can prevent further visual *** this research,using a Deep Neural Network(DNN),segmentation methods are proposed to detect the retinal defects such as exudates,hemorrhages,microaneurysms from digital fundus images and then the conditions are classified accurately to identify the grades as mild,moderate,severe,no PDR,PDR in ***,saliency detection is applied on color images to detect maximum salient foreground objects from the ***,structure tensor is applied powerfully to enhance the local patterns of edge elements and intensity changes that occur on edges of the ***,active contours approximation is performed using gradient descent to segment the lesions from the ***,the output images from the proposed segmentation process are subjected to evaluate the ratio between the total contour area and the total true contour arc length to label the classes as mild,moderate,severe,No PDR and *** on the computed ratio obtained from segmented images,the severity levels were ***,statistical parameters like the mean and the standard deviation of pixel intensities,mean of hue,saturation and deviation clustering,are estimated through K-means,which are computed as features from the output images of the proposed segmentation *** these derived feature sets as input to the classifier,the classification of DR was ***,a vGG-19 deep neural network was trained and tested using the derived feature sets from the KAGGLE fundus image dataset containing 35,126 images in

关键词： Diabetic retinopathy saliency map structure tensor gradient descent method exudates haemorrhages microaneurysms vGG-19

Geospatial analysis of forest fragmentation in Uttara Kannada District, India

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Forest Ecosystems 2016年第3期3卷 206-220页

作者： Ramachandra t v Bharath Setturu Subash Chandran Energy & Wetlands Research Group Center for Ecological Sciences（CES） Indian Institute of Science Centre for Sustainable technologies (astra) Bangalore Karnataka 560 012 India Centre for infrastructure Sustainable Transportation and Urban Planning（CiSTUP） Indian Institute of Science Bangalore Karnataka 560 012 India

Background： Landscapes consist of heterogeneous interacting dynamic elements with complex ecological, economic and cultural attributes. these complex interactions help in the sustenance of natural resources through bio-geochemical and hydrological cycling. the ecosystem functions are altered with changes in the landscape structure, Fragmentation of large contiguous forests to small and isolated forest patches either by natural phenomena or anthropogenic activities leads to drastic changes in forest patch sizes, shape, connectivity and internal heterogeneity, which restrict the movement leading to inbreeding among Meta populations with extirpation of species. Methods： Landscape dynamics are assessed through land use analysis by way of remote sensing data acquired at different time periods. Forest fragmentation is assessed at the pixel level through computation of two indicators, i.e., Pf （the ratio of pixels that are forested to the total non-water pixels in the window） and P~ （the proportion of all adjacent （cardinal directions only） pixel pairs that include at least one forest pixel, for which both pixels are forested）. Results： Uttara Kannada District has the distinction of having the highest forest cover in Karnataka State, India. this region has been experiencing changes in its forest cover and consequent alterations in functional abilities of its ecosystem. temporal land use analyses show the trend of deforestation, evident from the reduction of evergreen - semi evergreen forest cover from 57.31% （1979） to 32.08 % （2013） Forest fragmentation at the landscape level shows a decline of interior forests 64.42 % （1979） to 25.62 % （20] 3） and transition of non-forest categories such as crop land, plantations and built-up areas, amounting now to 47.29 %. PCA prioritized geophysical and socio variables responsible for changes in the landscape structure at local levels. Conclusion： terrestrial forest ecosystems in Uttara Kannada District of Central Western Ghats have be

关键词： Land use dynamics Forest fraqmentation Interior forests Biodiversity Geophysical variables

to deformation vector special solution in mining subsidence and ground and rock movements

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中国有色金属学会会刊：英文版 2005年第S1期15卷 294-298页

作者： v. Sedlák P. Blit'an technical University of Koice Faculty of Mining Ecology Process Control & Geotechnologies Institute of Geodesy & GIS Park Komenského 19 SK-04384 Koice SlovakiaTechnical University of Koice Faculty of Mining Ecology Process Control & Geotechnologies Institute of Geodesy & GIS Park Komenského 19 SK-04384 Koice Slovakia

the paper presents some specific procedures in modelling a deformation vector at deformation investigation of various engineering structures, buildings or terrain surfaces which are exposed by abiotik factors, for example by underground mining activities or recent geotectonic movements. A specific problem in deformation measurements is solved, when the same conditions of a monitoring network structure cannot be kept during all periodic observations.

关键词： deformation vector mathematical modelling geodetic periodic monitoring

Role of monovalent co-dopants on the PL emission properties of YAl_3(BO_3)_4:Ce^(3+) phosphor

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Journal of Rare Earths 2014年第10期32卷 927-932页

作者： R.Satheesh Kumar v.Ponnusamy v.Sivakumar M.t.Jose Department of Physics Anna UniversityM.I.T. Campus Research and Development Laboratory Department of PhysicsSaveetha Engineering College Radiological Sefety Division Indira Gandhi Centre for Atomic Research

the cerium （Ce3＋） doped yttrium aluminium borate （YAB） phosphor was synthesized by modified solid state reaction. the phosphor＇s phase purity and its emission properties were studied using powder X-ray diffraction pattern and photoluminescence spectroscopy. the synthesized YAB had rhomobohedral crystal structure. the phosphor had two different excitation and emission spectra. By 325 nm excitation, the phosphor had emission at 373 nm and with 363 nm excitation; the phosphor gave violet-blue emission at 418 nm. the Uv emission of the phosphor originated due to Ce3＋ ions at the yttrium site and violet-blue emission owing to Ce3＋ ions at non-regular sites viz., A13＋ and interstitial sites. the emission intensity of the phosphor was enhanced when monovalent ions （K＋, Na＋, and F） were added as co-dopants. the crucial role of ionic radii of monovalent co-dopants on the emission enhancement of the YAB：Ce3＋ phosphor was reported. thermogravimetric study showed that the YAB possessed high thermal stability at up to 900 ℃.

关键词： yttrium aluminium borate cerium monovalent codopants ionic radii thermogravimetric analysis rare earths

Large signal of h → μτ within the constraints of e_(i) → e_(j)γ decays in the 3-3-1 model with neutral leptons

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Chinese Physics C 2022年第12期46卷 106-125页

作者： H.t.Hung D.t.Binh H.v.Quyet Department of Physics Hanoi Pedagogical University 2Phuc YenVinh Phuc 15000Vietnam Institute of theoretical and Applied Research Duy Tan UniversityHanoi 10000Vietnam Faculty of Natural Science Duy Tan UniversityDa Nang 50000Vietnam

In the framework of the 3-3-1 model with neutral leptons,we investigate lepton-flavor-violating sources based on the Higgs mass spectrum,which has two neutral Higgs identified with the corresponding ones of the two-Higgs-doublet *** note that at the 13tev scale of the LHC,the parameter space regions satisfy the experimental limits of e_(i)→e_(j)γ*** regions depend heavily on the mixing of exotic leptons but are predicted to have large h_(1)^(0)→μτ*** also show that Br(h_(1)^(0)→μτ)can reach a value of 10^(-4).

关键词： Higgs boson electroweak interaction beyond the SM LFv decays

Kinetics and Structure of Refractory Compounds and Alloys Obtained by Mechanical Alloying

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Journal of Materials Science & technology 2001年第1期17卷 63-64页

作者： A.A.Popovich v.P.Reva t.A.Popovich O.v Arestov Far Eastern State technical University 10 Pushkin Street 690600 VladivostokRussia

Refractory compounds are material with interesting properties for structural applications. However, the processing of Such material is a great challenge because of their high melting temperature and limited ductility. Mechanical alloying is a novel technique of producing refractory compounds with specific properties. Kinetical and structural peculiarities of refractory compounds and alloys obtained by mechanical alloying are discussed.

关键词： mechanical alloying specific properties melting temperature great challenge

Energy Proficient Reduced Coverage Set with Particle Swarm Optimization for Distributed Sensor Network

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Computer Systems Science & Engineering 2023年第5期45卷 1611-1623页

作者： t.v.Chithra A.Milton Department of Computer Science and Engineering Arunachala College of Engineering for WomenManavilaiTamil Nadu629203India Department of Electronics and Communication Engineering St.Xavier’s Catholic College of EngineeringChunkankadaiTamil Nadu629003India

Retransmission avoidance is an essential need for any type of wireless *** retransmissions induce the unnecessary presence of redundant data in every accessible *** storage capacity is symmetrical to the size of the memory,less storage capacity is experienced due to the restricted size of the respective *** this proposed work,we have discussed the integration of the Energy Proficient Reduced Coverage Set with Particle Swarm Optimization(PSO).PSO is a metaheuristic global search enhancement technique that promotes the searching of the best nodes in the search *** is integrated with a Reduced Coverage Set,to obtain an optimal path with only high-power transmitting *** Proficient Reduced Coverage Set with PSO constructs a set of only best nodes based on the fitness solution,to cover the whole *** proposed algorithm has experimented with a different number of *** has been made between original and improved algorithm shows that improved algorithm performs better than the existing by reducing the redundant packet transmissions by 18%~40%,thereby increasing the network lifetime.

关键词： Wireless sensor network reduced coverage set swarm intelligence particle swarm optimization energy consumption

Physical vapor transport growth and morphology of Bi2Se3 microcrystals

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Particuology 2016年第3期14卷 118-122页

作者： v.v. Atuchin S.v. Borisov t.A. Gavrilova K.A. Kokh N.v. Kuratieva N.v. Pervukhina Laboratory of Optical Materials and Structures Institute of Semiconductor Physics SB RAS Novosibirsk 630090 Russia Functional Electronics Laboratory Tomsk State University Tomsk 634050 Russia Laboratory of Semiconductor and Dielectric Materials Novosibirsk State University Novosibirsk 630090 Russia Laboratory of Crystul Chemistry Institute of Inorganic Chemistry SB RAS Novosibirsk 630090 Russia Laboratory of Nanodiagnostics and Nanolithography Institute of Semiconductor Physics SB RAS Novosibirsk 630090 Russia Laboratory of Crystal Growth Institute of Geology and Mineralogy SB RAS Novosibirsk 630090 Russia Geology and Mineralogy Department Novosibirsk State University Novosibirsk 630090 Russia Spintronics Laboratory Saint Petersburg State University Saint Petersburg 198504 Russia Laboratory of Research Methods of Composition and Structure of Functional Materials Novosibirsk State University Novosibirsk 630090 Russia

High-quality Bi2Se3 microcrystals were grown by the physical vapor transport （Pvt） method without using a foreign transport agent. the microplate crystals grown under the optimal temperature gradient are well faceted and have dimensions up to -200 μm, the growth proceeds by the layer-by-layer mecha- nism with the formation of flat low-growth rate facets. the phase composition of the grown crystals was identified by the X-ray single crystal structure analysis in space group R3m, a = 4.1356（3）, C= 28.634（5）A, Z=3 （R=0.0147）. the most probable twin planes in the tetradymite structure were evaluated by the pseudo translational sublattice merhad.

关键词： Bi2Se3 Physical vapor transport Structure twin

On Wiener Index of Unit Graph Associated with a Commutative Ring

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Algebra Colloquium 2022年第2期29卷 221-230页

作者： t.Asir v.Rabikka Huadong Su Department of Mathematics-DDE Madurai Kamaraj University Madurai 625021Tamil NaduIndia School of Science Beibu Gulf University QinzhouGuangxi 53501lChina

Let R be a ring with non-zero *** unit graph of R,denoted by G(R),is an undirected graph with all the elements of R as vertices and where distinct vertices x,y are adjacent if and only if x+y is a unit of *** this pap... 详细信息

关键词： unit graph distance Wiener index hyper-Wiener index