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classification of Glaucoma in Retinal Images Using Efficientnetb4 Deep Learning Model

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computer Systems Science & Engineering 2022年第12期43卷 1041-1055页

作者： A.Geetha n.b.Prakash national Engineering college Kovilpatti628502India

Today, many eye diseases jeopardize our everyday lives, such as Diabetic Retinopathy (DR), Age-related Macular Degeneration (AMD), and *** is an incurable and unavoidable eye disease that damages the vision ofoptic nerves and quality of life. classification of Glaucoma has been an active fieldof research for the past ten years. Several approaches for Glaucoma classification areestablished, beginning with conventional segmentation methods and feature-extraction to deep-learning techniques such as convolution neural networks (cnn). Incontrast, cnn classifies the input images directly using tuned parameters of convolution and pooling layers by extracting features. but, the volume of training datasetsdetermines the performance of the cnn;the model trained with small datasets,overfit issues arise. cnn has therefore developed with transfer learning. The primary aim of this study is to explore the potential of Efficientnet with transfer learning for the classification of Glaucoma. The performance of the current workcompares with other models, namely VGG16, InceptionV3, and Xception usingpublic datasets such as RIM-OnEV2 & V3, ORIGA, DRISHTI-GS1, HRF, andAcRIMA. The dataset has split into training, validation, and testing with the ratioof 70:15:15. The assessment of the test dataset shows that the pre-trained Efficientnetb4 has achieved the highest performance value compared to other models listedabove. The proposed method achieved 99.38% accuracy and also better results forother metrics, such as sensitivity, specificity, precision, F1_score, Kappa score, andArea Under curve (AUc) compared to other models.

关键词： convolution neural network deep learning fundus image glaucoma image classification

RAPID SOLIDIFIcATIOn OF HYPEREUTEcTIc SILVER-cOPPERALLOY In DROP TUbE

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Acta Metallurgica Sinica(English Letters) 1999年第3期12卷 251-258页

作者： Wang, n. Wei, b. northwestern Polytechnical Univ Xi'an China

The Ag-50wt%cu hypereutectic alloy was solidified and investigated in a 3 m drop tube, and its nucleation and microstructure characteristics were explored also. The results showed that (1) with the decrease of droplet size, the structural morphology transforms from the dendrites with long trunk and thin short secondary arms to fine dendritic structures; (2) the dendritic growth is mainly controlled by solute diffusion within the whole undercooling regime, while the influence of thermal diffusion-controlled growth becomes stronger above a critical undercooling about 268 K; (3) the refinement of dendritic structure is caused by large amounts of nuclei within droplet; (4) when droplet diameter is smaller than 300 micron, the undercooling and growth velocity were estimated to be greater than 268 K and 290 mm/s respectively, while the solute trapping effect may occur.

关键词： Eutectics Morphology Rapid solidification

Investigations on luminescence of rare earths doped caTiO_3:Pr^(3+) phosphor

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Journal of Rare Earths 2010年第4期28卷 488-492页

作者： n. Suriyamurthy b.S. Panigrahi Radiological Safety Division Technical Services Division Indira Gandhi Centre for Atomic Research Kalpakkam-603 102 India

calcium titanate doped with praseodymium was prepared through solid state reaction and it exhibited intense red emission at 612 nm. Phosphors were characterized for photoluminescence, thermo-luminescence and afterglow emissions. Study of effects of rare earths on photoluminescence as well as afterglow intensity was reported. Presence of gadolinium enhanced luminescence. Presence of some monovalent ions enhanced both afterglow and photoluminescence emission. Thermo-luminescence glow curves were analyzed and ...

关键词： perovskites calcium titanates red afterglow rare earths

Studies of two lanthanide coordination polymers built up from dinuclear units

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Journal of Rare Earths 2013年第1期31卷 85-93页

作者： b.benmerad K.Aliouane n.Rahahlia A.Guehria-Ladoudi S.Dahaoui c.Lecomte Laboratory of crystallography and Thermodynamic Department of chemistry Faculty of ScienceUniversity A. MIRABejaa cRM2 UMR-CNRS 7036Institut Jean BarriolUniversity Nancy I

The two three-dimensional oxo-bfidged lanthanides {[Ln2（c4H2O4）3（H20）4]· 3H2O}3, with Ln=Ho3＋（1）; Gd3＋（2）, are isomorphous. They have layer-type structures built up from non-centrosymrnetric dinuclear unit Ln2O12（H2O）4, beside three lattice H20 molecules stabilizing the 3D open-frmnework. The building entities are linked through one classical syn-anti g2-carboxylato-K1O：K^1O＇ bridge. Within the bi-polyhedra, two double μ2-O＇; K2O,O＇ bridges and a syn-syn classical one, support the magnetic measurements carried out on holmium compound indicating relatively weak anti-ferromagnetic interactions. The compari- son with magnetic studies on the almost similar reported Gd（III） compound, suggested that concomitant antiferromagnetic and ferro- magnetic properties could not be excluded. The two distinct thermal behaviors evidenced the higher metal-water bond strength with the smaller cation, and revealed the great supramolecular effects generated by hydrogen-bonding patterns.

关键词： lanthanide organic frameworks crystal structure thermal behavior magnetic interactions rare earths

combining material characterization with single and multi-oxyanion adsorption for mechanistic study of chromate removal by cationic hydrogel

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Journal of Environmental Sciences 2011年第6期23卷 1004-1010页

作者： Irene M.c.Lo Samuel c.n.Tang Department of civil and Environmental Engineering The Hong Kong University of Science and TechnologyHong KongChina

cationic hydrogel with magnetic property was synthesized via radical polymerization and its removal capacity of chromate from contaminated water was found to be 200 mg/*** Fourier transform infrared spectroscopy（FT-IR） study,the mechanism of chromate removal by hydrogel was found to be non-specific adsorption,mainly due to ion exchange,as evidenced by the positively charged functional group,trimethyl ammonium-n＋（cH3）3,in the *** were accordingly determined by testing di？erent oxyanion adsorption onto the *** results of the chromate adsorption experiments illustrated that the amount of chromate adsorbed was nearly equal to that of the chloride released from the hydrogel,which is part of the evidence for ion *** and multi-oxyanion adsorption experiments were also performed,and it was demonstrated that ion removal was species independent,but charge dependent,another characteristic of the ion exchange *** was found that the same Langmuir model can be applied to best fit the findings of single and multi-oxyanion adsorption,which further indicates the mechanism of chromate removal is attributed to ion *** view of the above,the background anions compete for adsorption sites with chromate,evidenced by inhibitive chromate removal in the presence of background electrolytes in the batch studies,further echoing the ion exchange mechanism.

关键词： adsorption magnetic hydrogel mechanism ion exchange oxyanion

Plastic Strain Energy Model for Rock Salt Under Fatigue Loading

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Acta Mechanica Solida Sinica 2018年第3期31卷 322-331页

作者： M.M.He n.Li b.Q.Huang c.H.Zhu Y.S.chen Institute of Geotechnieal Engineering Xi'an University of TechnologyXi'an 710048China State Key Laboratory of Eco-hydraulics in northwest Arid Region Xi'an University of TechnologyXi'an 710048China college of Information Engineering and Automation Kunming University of Science and TechnologyKunming 650500China Shaanxi Key Laboratory of Loess Mechanics and Engineering Xi'an University of TechnologyXi'an 710048China

The fatigue test for rock salt is conducted to investigate the effects of stress ampli- tude, loading frequency and loading rate on the plastic strain energy, from which the evaluation rule of the plastic strain energy is analyzed, which is divided into three stages： cyclic hardening, saturation and cyclic softening. The total accumulated plastic strain energy only depends on the mechanical behavior of rock salt, but is immune to the loading conditions. A novel model for fatigue life prediction is proposed based on the invariance of the total plastic dissipation energy and the stability of the plastic energy per cycle.

关键词： Rock salt Fatigue life Plastic energy

Large dinosaur egg accumulations and their significance for understanding nesting behaviour

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Geoscience Frontiers 2024年第5期15卷 467-488页

作者： L.Ezquerro R.coimbra b.bauluz c.núñez-Lahuerta T.Román-berdiel M.Moreno-Azanza Departamento de Geodinámica Estratigrafía y PaleontologíaFacultad de Ciencias GeológicasUniversidad Complutense de MadridC/JoséAntonio Novais1228040MadridSpain Aragosaurus-IUcA:Recursos Geológicos y Paleoambientales.Departamento de ciencias de la Tierra.Facultad de ciencias Universidad de ZaragozaC/Pedro Cerbuna 1250009 ZaragozaSpain Museu da Lourinha LourinhaPortugal GeobioTec Department of Earth SciencesNOVA School of Science and TechnologyUniversidade Nova de LisboaCaparicaPortugal GeobioTec Departamento de GeocienciasUniversidade de AveiroAveiroPortugal Insitut catalàde Paleoecologia Humana i EvolucióSocial(IPHES-cERcA) Zona Educacional 4Campus Sescelades URV(Edifici W3)43007 TarragonaSpain Departament d´Història i Història de l´Art Universitat Rovira i VirgiliAv.Catalunya 3543002 TarragonaSpain Geotransfer IUcA Departamento de Ciencias de La TierraFacultad de CienciasUniversidad de ZaragozaZaragozaSpain

The accurate identification of dinosaur egg accumulations as nests or clutches is crucial for understanding the reproductive behaviour of these extinct ***,existing methods often rely on the presence of complete eggs and embryo remains,and sedimentological criteria that are only applicable to well-structured *** this study,we introduce an innovative approach to characterize egg accumulations in structureless sediments,where traditional nest structures may not be *** methodology employs a unique combination of sedimentological,taphonomic,geochemical,and geophysical proxies for the study of egg *** applied this approach to the egg accumulation from Paimogo(Jurassic,Portugal),traditionally interpreted as a *** findings reveal that the Paimogo egg assemblage is a secondary deposit,resulting from a flooding event in a fluvial plain that dismantled several allosauroid and crocodylomorph *** eggshell vapor conductance results,coupled with sedimentological evidence,suggest that allosauroid dinosaurs buried their eggs in the dry terrain of overbank areas close to a main channel during the breeding season,likely during the dry season to prevent the embryos from *** research underscores the necessity of multidisciplinary approaches in interpreting egg accumulations and offers a novel methodology for studying these accumulations in structureless *** findings provide new insights into the breeding behaviour and nesting preferences of these extinct organisms,contributing to our understanding of dinosaur ecology.

关键词： breeding behaviour Theropod Taphonomy Stable isotopes Magnetic susceptibility Jurassic

Lanthanum-exchanged zeolite and clay as anticorrosive pigments for galvanized steel

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Journal of Rare Earths 2014年第4期32卷 352-359页

作者： S.Roselli n.bellotti c.Deyá M.Revuelta b.del Amo R.Romagnoli cIDEPInT(centro de Investigación y Desarrollo en Tecnología de Pinturas)(cOnIcET-cIc)

A wide variety of inhibitive pigments is now being offered as possible alternatives to chromate and lead compounds for painted metals protection. Unfortunately, the most wide spread of these substitute pigments, zinc phosphate, has, at present, raised some environmental concern because phosphate causes the eutrophication of water courses and zinc itself is toxic. The aim of this re-search was to study the anticorrosive performance of a mixture consisting of zinc phosphate, modified zeolite and clay （bentonite） in order to diminish phosphate content in paints. The zeolite and the clay were exchanged with La（III） ions, as inorganic green inhibitor. In the first step, the anticorrosion protection by La（III） ions in solution was assessed by electrochemical tests. In the second step, an epoxy-polyamide paint formulated with the pigment mixture applied on galvanized panels was studied by salt spray test and electro-chemical noise measurements （EnM）. The results showed that it was possible to replace part of the zinc phosphate content in the paint with the exchanged zeolite and the clay.

关键词： exchanged pigments corrosion anticorrosive paints electrochemical noise measurements rare earths

chloride binding and time-dependent surface chloride content models for fly ash concrete

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Frontiers of Structural and civil Engineering 2016年第1期10卷 112-120页

作者： S. MUTHULInGAM b. n. RAO Department of civil Engineering SSN College of Engineering Kalavakkam 603 110 India Structural Engineering Division Department of Civil Engineering Indian Institute of Technology Madras Chennai 600 036 India

corrosion of embedded rebars is a classical deterioration mechanism of reinforced concrete structures exposed to chloride environments. Such environments can be attributed to the presence of seawater, deicing or sea-salts, which have high concentrations of chloride ion. chloride ingress into concrete, essential for inducing rebar corrosion, is a complex interaction between many physical and chemical processes. The current study proposes two chloride ingress parameter models for fly ash concrete, namely： 1） surface chloride content under tidal exposure condition; and 2） chloride binding. First, inconsistencies in surface chloride content and chloride binding models reported in literature, due to them not being in line with past research studies, are pointed out. Secondly, to avoid such inconsistencies, surface chloride content and chloride binding models for fly ash concrete are proposed based upon the experimental work done by other researchers. It is observed that, proposed models are simple, consistent and in line with past research studies reported in literature.

关键词： binding isotherms chloride ingress concrete fly ash surface chloride content